EXPLAINED: PCIe lane SWITCHING & Biggest MISTAKES! | Don't DO IT 👉 WRONG slot for m.2 SSD!

[@theTechNotice]

CORRECTION: Ryzen 7000 has 24+4 PCIe Gen 5 lanes instead of 20+4 what I said in the video. Thank you everyone for pointing that out! 😊

[@Matlockization]

I honestly don't understand why you have background music playing when you're trying to explain something important. The background music makes it very hard to hear what you are saying and adds to the confusion of this video.

[@mytech6779]

Threadripper is 120+8 or 60+4 (older not Pro). In the modern AMD structure every type of input/output device is connected through PCIe. So even on Threadripper the chipset lanes are still used for small peripheral connections that are not expected to have good latency and are not consistently moving enough data to justify reserving direct lanes for each device (x1 x2 or x4).

[@cynicalaries6201]

Do you have the link for the other video you did on the PCle lanes in more detail? You do a great job explaining.

[@barbatocedric4246]

A litle late but . . . Ryzen 7000 have 24+4 (total 28) witch can only be totally in use with X670E. 20+4 (total 24) was the 3000 and 5000 series. The 1000 and 2000 was having 16 in total. You can have 1 GPU at gen 5x16 and 2 SSD NVME at gen 5x4 and the other via the chipset (can go to 2 gen 4 x4 as gen 5 x4 have double the bandwith).

[@dipi71]

PCI and its variants are bus protocols. Components connect to the bus. What's presented in the video sounds more like point-to-point connections (lanes ostensively »come from the CPU« or »come from the chipset«). This Tech Notice explanation does not make sense.

[@Babicoste]

Easier method: I always check the Tech Spec -> Storage Section on their product website or the manual about M.2 slot before adding extra storage: My Asus ROG Strix B450-F Gaming Tech Spec: *3 When the M.2_1 Socket 3 is operating in SATA or PCIE mode, SATA6G_5/6 ports will be disabled. *4 When the M.2_2 is occupied by M.2 device, PCIe x16_1 will run at x8 mode. I don't want to give up the pcie lane for my GPU, so I bought a 2.5 SATA SSD as a secondary storage instead

[@singwolf.]

Here are the spech of my MSI B650 th 3x M.2 (Qty) M.2_1 Source (From CPU) supports up to PCIe 4.0 x4 , supports 2280/2260 devices M.2_2 Source (From CPU) supports up to PCIe 4.0 x4 , supports 2280/2260 devices M.2_3 Source (From Chipset) supports up to PCIe 4.0 x4 , supports 2280/2260 devices 6x SATA 6G (Qty) • M2_2 supports PCIe 4.0 x2 speed when Ryzen™ 5 8500G is installed so i can run a secondary nvme as storage?

[@pacocarrion7869]

@@singwolf. sure, but I'm not sure the performance of M.2_3, have you tested?

[@kaseyboles30]

Actually they should move most primary slots for gpus to x8. No card yet uses the full bandwith of gen4x8 let alone of gen5. Few need more than gen3x4, and even those don't show much fps drop.

[@joshhardin666]

long story short, mainstream platforms have insufficient pcie lanes for common uses. with all current mainstream platforms, you get 3 pcie slots and up to 3 m.2 slots. typically a 16x gpu is going to be in the top pcie slot. if you put a card in the second pcie slot it will half the bandwidth to the first (gpu) pcie slot to 8x. this is UNACCEPTABLE, particularly now that we have cards with good memory bandwidth. the third pcie slot is a 4x slot (which can sometimes look like an 8x or 16x slot but it's electrically only 4 lanes). this is typically shared with the second m.2 slot (at least it is on amd platforms) this means if you have a high bandwidth m.2 drive slotted in the second m.2 slot, it will have to share bandwidth with whatever is in that 3rd pcie slot. this too is unacceptable because that could very well be a multi 4k capture card, or another m.2 ssd on an adapter pcie card. the top slot (at least on amd boards) is direct cpu connected in every case i've seen, the THIRD m.2 slot is typically connected through the chipset which means it has to contend with your onboard 10g nic, your audio solution, your onboard usb3.2/4, etc. etc. which can slow things down quite a bit. tl;dr: intel and amd need to start giving us more pcie lanes on these platforms. 64 or so should do it, that should at least give us 3 real 16x pcie slots, 3 m.2 slots that aren't switched, and a dedicated pcie 4x to onboard dual 10g networking so it doesn't slow anything down. there are lots of people like myself that are peeved that they'd have the audacity to charge us something like another THOUSAND dollars just to get reasonable numbers of pcie lanes and a couple extra memory channels.

[@snkbnk]

There is a small mistake in the information you provided regarding the AMD 7000 CPU. Number of PCI lanes is 24+4. Not 20+4.

[@dismuter_yt]

That's not a small mistake though 😅

[@theTechNotice]

Yes, you are right, thanks for pointing that out!

[@wotreplays8896]

​@@dismuter_yt Yes, he enjoys making fun of JayzTwoCent's errors in some of the videos, but the motherboard he suggested can't read some of my hard drives, so I'm considering sending him the bill right now. ;))

[@jirehla-ab1671]

If i set the pcie slot to x8x4x4 & i install a dual nvme expansion card on the slot what will happen?​@@theTechNotice

[@klayed]

@@wotreplays8896 send 2 bills i need a new motherboard also

[@appuswami6611]

I am very glad there is Tech Notice out here making these kind of videos for creators. Everybody else talks only about gamer pcs. Anyhow even though I am still confused I at least know where to start looking - Block Diagrams. Thank you Tech Notice for making such videos and engaging in the comment section.

[@theTechNotice]

appreciate the comment, you're exactly who I'm making these videos for! :)

[@WiscoMadman]

This comment right here. I second that sir! Thank you!

[@michaelgleason4791]

This video was a lot of word salad. Just check your motherboard manual.

[@WiscoMadman]

@@michaelgleason4791 actually I found it fairly helpful considering, as a first time builder, I didn't know a lot of this.

[@klayed]

@@theTechNotice does that mean u dont like us gamers huh

[@danielagius6634]

Excellent video. One of the most informative channels out there. Well done.

[@shanent5793]

There are PCIe 5.0 peripherals: the NVIDIA H100 GPU and ConnectX-7 NIC, and several SSDs. You should note that the x16 connection on Intel LGA1700 can only be bifurcated x8/x8, which is less flexible than AM5 which allows x4/x4/x4/x4

[@mytech6779]

I have an old 990fx AM3+ board (The northbridge provides all PCIe) and it has 40+4 PCIe2.0 lanes (data is sparse so a bit of collecting data and calculating on my part). The 990 chipset could support(based on board vender), either 2 x16 ; x8/x8/x16 ; or x8/x8/x8/x8. x32 is in the PCIe standard but I don't know of any x32 devices. and still had 2 x4 and 2 x1 (or the option of 1 x4 and 6 x1 ) for expansion cards 2 or 4 PCIe lanes (unclear they renamed it alink-Express3), were used for the southbridge which handles all of the network(1Gb), USB(~10 mix of 2.0 and 3.0), 6-SATA, firewire, eSATA, audio and several legacy headers for things like serial and parallel.

[@firsh]

@@mytech6779 I think it was "easier" with earlier gen PCIE to offer more lanes because things were slower. But at least it could be spread more flexibly, I recall old mobos having like 5 expansion slots much like as shown in the video of the HEDT mobo. And back then there was no m2, less competition for lanes. But with each gen, the bandwidth doubles. The fact that the lane count is not halving means that they are indeed improving, but with the limited nr of lanes it's harder to allocate them to everything (like USB4 itelsef takes 4x from the getgo).

[@antonmarriott5641]

Question?: The MSI Mag Tomahawk Wifi DDR5 MAX does not have a cpu connected pci4 nvme slot other than slot 1. So the question is which is more beneficial having the main hard drive connected directly to cpu and leaving only 8 lanes for gpu; or connecting main hard drive to chipset and having 16 lanes for gpu? Articles I've seen so far seem to indicate a negligible performance difference between 8 lanes and 16 lanes for gpu usage, but I don't really see anything about the latency difference between using chipset or cpu for ssd...or combined evaluation. Right now I have a i7-12700K and rtx3050 so slot 1 for my nvme is for me as 3050 only uses 8 lanes anyway, but I am planning on upgrading in the future. Primarily used for gaming, but also learning python and GIS (GIS rendering seems intensive).

[@lolohasan6424]

I have a 7950X3D, 1x 980Pro 1TB PCI 4.0 , 1x 970 Evo 1TB PCI 3.0, 1x Kingston 500 GB PCI 4.0, RTX 4070Tİ on a MSI B650 Tomahawk wifi and I can use my all SSD at full speed and performance PCIe 4.0 @x4 speed. And I can use my RTX 4070Ti @ x16 Gen 4.0

[@567davefair]

Ryzen 7000 series has 24+4 lanes to CPU. 16x lanes for PCIe, 8x lanes NVMe and 4x to chipset. On the x670e you have two "dedicated" M.2 slots to the CPU so no lane switching(sharing).

[@TheOneGhost12]

Even if it’s a gen 5 m.2 ? So the x670e aorus master board ? Do you happen to understand the diagram on that bored ? I can use full 16 lanes for gpu and can I use either gen 5 or gen 4 to cpu without lane switching? Thanks so much if you know

[@firsh]

X670E still going strong for those that prefer storage over the USB4 of X870E which actually reintroduces this problem.

[@naturalgeocrappic5179]

Thanks - very useful

[@theTechNotice]

Thank you! 🙂

[@jamestaylor3805]

MSI Tomahawk has some interesting potential for tweaked graphics performance due how it's laned with a direct to CPU slot and a chipset wired slot. Would be a great board for exploring the real difference in performance from various lane routing.

[@ricardobimblesticks1489]

Great just picked up a z790 tomahawk, so my options are - 1. Read the manual or 2. Spend hours tinkering and benchmarking. Looks like I'm gonna need more coffee :D

[@robertnelson3179]

Thanks for reviewing and clearing this up. I had chosen one of the gigabyte boards you recommended and had to make sure the SSd was in right slot to keep it going.

[@kdkiller98]

This was a great video good job. first time in a long time i learned something new from youtube. Definitely subscribing

[@tomquimby8669]

Gigabyte some of them- Yes z790 elite x has gen 4 m.2 top slot and 16 lane to first graphics card slot. so no switching! Good video as this confuses so many people

[@SoneliasT]

Some motherboards lose SATA ports if extra M2 slots are used. It is not only a reduction in lanes for the graphics card slot that can be lost

[@theTechNotice]

True!

[@DurokSubaka]

Spoiler, Gamers Nexus did a video of this and it’s called PCIE bifurcation and the performance drops from X16 to X8 were negligible literally almost unmeasurable.

[@kaede15]

This is my main issue for years, can't afford a threadripper, but the difference in # of PCIe Lanes between Threadripper and Ryzen is just ridiculous. Every gen upgrade AMD is adding 4 miserable lanes to the Ryzen line.... People need at least 2 full PCIe 16x and a 3erd at least 8x. Not including m.2 of course. Every system I built I have to choose between, fast network cards or storage HBA, and that always comes with a sacrifice of my GPU PCIe bandwidth by HALF which is around 5-10% perfornmace....

[@leenagle2903]

Nobody needs 2x16 slots. Gaming. Sli/xfire is dead Productivity no card out there saturates pcie 4.0 8x let alone 16x

[@juanestebanmascietti8360]

Amazing info.. well explained. Love you son cameo at 15:10 second.

[@blessedjunior6989]

I really tried but i got morr confused but i will rewatch again

[@shanemcknight1583]

Very good info on this! As a creator, this knowledge is very helpful on discerning your system and quite useful when building one and choosing the right motherboard that will be a benefit to your area of work.

[@LorentGuimaraes]

TL:DR: If you are building a gaming PC, just get a board without any gen 5 nvme slots and you are safe. Why on earth any gaming PC needs gen 5 SSD is beyond me.

[@CoolMinded-f2d]

After studing it for 3hours,I am a genius in this topics now..thanks man❤

[@YamieX]

I have a Z690 Aero G DDR4 with a 12th Gen 12700K, and I was just looking at the recent Z790 boards and noted that the recent Z790 can reduce the top slot and was wonder why they went with the design. As I have populated all my 4 M.2 slots, I was quite surprised by the recent Z790 update, as it will be a concern if a creator needs the additional M.2, will have to choose between the m.2 and GPU. Hope that they will consider to review the reduction by the PCIE lane in future.

[@onoffgeorg9828]

these z790 mobos are garbage....its crazy a m.2 disk slow down gpu. i have 2 m.2 disks in z270 p asus and no slow down in gpu

[@temp50]

18:14 Very bold statement. I have the same card (Hyper M.2 X16 gen 4) and it doesn't have a PLX chip on it. It means that if you wanna use the 4 M.2 slots on the boards, you have to bifurcate the given PCI-E X16 to 4x4. Are you sure that the motherboard supports bifurcation for EVERY X16 slot? Because they are usually supporting it only on the first X16 slot but not the other ones, even if those lanes are also connected to the CPU and not the chipset. Slots connected to the chipset are most probably not supporting PCI-E bifurcation at all.

[@sitaroartworks]

16:22 - exactly. In less words, the former southbridge is integrated inside the CPU socket making all of it like a sort of cortex. There is no latency between the CPU and the components on the PCI-E lanes.

[@xGamerGeek]

Late to the party, but was actually wondering about this, since ive seen people not using the top ssd slot. And then this video shows up on my feed today! Thanks for the info😊

[@JTL1776]

Wondering why we cant have a Z790 gaming board with 3 PCIE lanes. Like GPU. But i want to add a Capture and Sound Card. Why when we pay 500 to 1000 for the motherboard do we have to compromise on Whats parts we can add to our pc.

[@sabishiihito]

There are several Z790 gaming boards that have 3 full length PCIe slots, though obviously they're not all x16 due to the platform not having enough lanes. Z790 Aorus Master and Tachyon, MSI Z790 MEG Ace and Asus ROG Maximus Hero (not the newer Dark) come to mind immediately. Now, if you're asking why the mainstream platforms don't have all those PCIe lanes? Well, AMD and Intel want you to buy their HEDT or workstation platforms (=more $$$ for them) if you want more bandwidth.

[@bharumusic]

Great video!! I really needed to know a lot of this information right now for a build I want to do 🙏🏾

[@hugheffo]

So just watching this, and I have a z790 motherboard with 13th gen i9. The CPU has 20 PCI lanes. 16 is being used by the graphic card and 4 is being used for the M.2 card. I also have another M.2, in the second slot, which is using 4 PCI lanes from the Z790 chipset. Both my graphics card and 1st M.2 card are both running at full speed, X16 (gen 4) for the GPU and X4 (gen 4) for the M.2

[@onoffgeorg9828]

your mobo is ok, other mobos have a garbage m.2 slot. when you put a disk to garbage m.2 slot, your gpu is slow down

[@Nicks_Hobbies_Channel]

I've spent days looking for this info for a few z790 boards. And you reviewed that specific board and made it clear how to connect the m.2 units in order not to reduce the PCIe_1 lanes

[@alrizo1115]

So if you're using the m.2 slot at the top of the gpu, there's no lane cut as long as it's a gen 4? So how about using the pcie slots below the top pcie slot? Will it cut the main to half if for example we add an m.2 there?

[@bogdan12275]

That’s what i need to know, i think it will be fine if it’s a Gen 4, i dunno I’m so bad at PCI-E Lanes lol. Just look it up in ur mb manual.

[@alrizo1115]

@@bogdan12275 if I understand it correctly, the 13th gen in particular, has has up to 1x pcie gen5 x16 and 1x pcie gen4 x4. So a 4th gen m.2 installed in the cpu chipset will not cut down the gpu lane. But if you use the extra pcie slots at the same time, I have no idea either

[@theTechNotice]

I think that's a good way of looking at it, but always double check the manual! :)

[@AlfaPro1337]

Dude, read the manual for clarification, it's on the web! For free! Intel 12th gen, introduced x16 Gen 5 + x4 Gen 4. Some motherboard, the top most (the closest to the CPU) wired it to Gen 5 lanes, while other Gen 4. AMD on the other hand, doesn't separate. Meaning, if you installed PCIE 4.0 devices, your entire CPU's PCIE will run at Gen 4 speed.

[@firsh]

Well explained! I wanted to point out that newer and more expensive chipset mobos are not necessarily better in this regard. For example, X870E has mandatory USB4 that readily takes away 4 lanes from the CPU. On X670E however, it's not mandatory (and can probably added later if needed as a card to a slot/chipset-side that has no switching), so it supports gen5 M.2 SSD slots better! Also, with the advent of gen5 GPUs (perhaps 50xx Nvidia, we'll soon find out), the halving to x8 will not matter that much, because bandwith-wise it'll be equal to gen4x16 which in itself is hard to saturate. Until then, with a gen4 normal GPU it's equivalent to putting them in a gen3x16 slot, with the switching's effect.

[@TheBigBlueMarble]

I have a pretty good understanding of PCIe lanes, but your explanation left me scratching my head.

[@SVT_LIGHTNING]

My msi z790 tomahawk I have all 4 pcie slots filled with 4 gen 4 drives and 2 sata drives. My 4090 runs at full speeds. My z490 tomahawk has both nmve slots filled and 4 sata drives it's only a pcie gen 3 "10th gen" and my 3080ti runs at full gen 3 speeds "3080ti is gen 4 but again 10th gen..." I've never had an issue with populating nvme slots and loosing lanes. Even on my old z170 and 6700k build.

[@Kazoom28]

Thanks for the clarification and reconfirming my thoughts which are the same as yours!

[@StreamVirtual]

Those proart boards have a big problem. The heats sink on the chipset sticks up too far and prevents pCie cards from properly seating in the second slot making the slot worthless. I have 4 of them and I'm thinking about chucking them all in the trash now.

[@ArunSingh-rr8fc]

you'll need to custom watercool and get a GPU block.

[@camjohnson2004]

Motherboard manuals mostly (not always) but mostly let you know when you are sharing PCIe lanes between different devices and slots, and in some cases, you will be given a block diagram of how the system devices are connected and if/when they overlap. Usually this is when you have 2 PCIe x16 slots on the board and want to run Dual GPUs, you have to switch 8 lanes from the main slot to the 2nd slot. Also some boards will take PCIe lanes away from the GPU slot to power additional high speed M.2 drives, (ASUS and Gigabyte do this on their top end boards). However, there are dedicated slots (PCIe and M.2) that do not share lanes, meaning you get full speed to those slots. on AMD systems, your Primary M.2 slot, (closest to the CPU) has its own dedicated PCIe lanes (AMD did this intentionally with Ryzen). Also, Ryzen 7000 and 9000 series have a total of 28 PCIe lanes off the CPU, 16 for the Primary GPU, 4 lanes for the Primary M.2 slot, 4 general purpose lanes (sometimes routed to a additional PCIe slot or to a 2nd CPU connected M.2 and then finally 4 lanes are used to connect the CPU to the Chipset. the Ryzen 1000, 2000, 3000 and 5000 series had a total of 24 lanes.

[@iDunnoMan9000]

This video is wild. You just explained so clearly something I didn't even know existed! 😅 Thank you!

[@MasterHomebrew]

I looked carefully at my Intel CPU 12900ks specs which is a 16+4 pci lane and my Asus Z690 rog hero board which indicates that all SSD NVme sticks are running through the chipset and none run off the 16 PCIe lane. Apparently Asus doesn't think that any Nvme SSD should run from that but rather the 4 lane chipset is sufficient. That means my GPU should get the full 16 lanes unless I was to plug something else into the PCIe lane or add another GPU. I believe this is correct. Please advise if I am wrong.

[@blahorgaslisk7763]

Note that a lot of motherboards for the AM5 socket and currently AMD Ryzen 7000 processors doesn't support PCIe 5.0 for the x16 slot for GPU or the first M.2 slot. Others support one M.2 at PCIe 5.0 but still only PCIe 4.0 for the x16 slot for GPU. Finally there are cards that support up to PCIe 5.0 for both the first M.2 and the PCIe x16 slot for the GPU. Note that this is present in both B650 motherboards and X670 motherboards. So check the documentation so you know what the capabilities of the motherboard is. The PCIe x16 only supporting up to 4.0 is today no big deal as currently there aren't any graphic cards that support PCIe 5.0. It might actually matter in a year or so when new graphics cards are released. But even then I doubt it will be a dramatic difference between running those cards at PCIe 4.0 or 5.0. The limit on the M.2 slot is however more real as there are very high performance M.2 drives that support PCIe 5.0. However we're talking about 7GB/s or 15GB/s, and while this sounds drastic it's not really something you are likely to feel the difference of in real life. Besides the maximum transfer rate tends to be limited in span on the fastest drives. Once you've filled the buffer on the drive the write speed will go down a lot. PCIe 5.0 drives also tend to use more energy and run a lot hotter than the PCIe 4.0 drives. What I'm trying to say is that there are speed limitations on the PCIe slots and the first M.2 slot on a lot of motherboards. And yet that doesn't necessarily mean that they are bad. But check the specs before you buy so you aren't surprised when PCIe is limited to 4.0 if you upgrade in the future.

[@Ignisan_66]

My Z790 motherboard MSI MAG Tomahawk Wi-Fi only has 1 M.2 gen 4 connection to the CPU so the x16 gen 5 lanes to the GPU don't need to switch.

[@Crossfire2003]

Great video! I always check the manual of the motherboard, and I usually choose Gigabyte.

[@tehsimo]

WHYYYYYYYYYYYYYYYYY do ASUS not give us the block diagrams?

[@gherbent]

Useful video. Although I knew some of the info, so many PC users live in negligence to know it.

[@Camrographer]

It’s not super critical for me as a photographer, but I was upset when I noticed that myASUS rogue maximus cut down, bandwidth or disabled I think two of my data ports Or cut their bandwidth down if I installed a second nvme drive. Especially since all my SATA ports are populated with drives. . I wonder if it’s worthwhile to buy a creator motherboard instead of a gaming one, and if it also provides additional headroom between upgrade periods because of all the additional slots.

[@deadlymarsupial1236]

Good video for noobs and this is very much a consideration that requires due diligence when comparing motherboards for above average builds and sadly vendors do not make this task quick and easy by lack of sufficient search criteria.

[@mikelascelle2921]

Nice vid. Helped alot. Wish my motherboard had a diagram like that and not just words

[@Vitis-n2v]

i have an Asus TUF b550 chipset motherboard and it has 2x m.2 slots and 6 sata slots. When i plug an M.2 SSD into the second slot it disables 2 of the sata ports and uses that to run the second m.2 slot. So i can have 2x M.2 + 4 Sata drives or 1x M.2 + 6 Sata drives. Also since the second m.2 slot uses bandwidth of 2 Sata ports it limits the second m.2 SSD to 1.5GB/s speed (single Sata 3 is 6gbps so 12gbps = 1,5GB/s).

[@PizzlesTechTime]

Really upset that I didn't end up getting the TR Pro. I was watching the videos and nothing was being talked about when it comes to liens switching after. I purchased it. Now everyone is talking about it.... Im stuck with a PC I hate working with now

[@pyromethious]

This is why researching your Board is probably the most important thing you can do when in the design phase. FYI, this has been a thing since at least the existence of PCI in general (AFAIK).

[@rlmtech]

Isn’t Intel 20 lanes plus the dmi lanes to the chipset? Therefore 16x5.0 for GPU and 4x4.0 for the first m.2 which is always dedicated… Everything else comes from the chipset ?

[@dizzywow]

Yes. The video is very misleading. There is no reduction in video card PCIe when using the first M.2 slot.

[@Fk8td]

The Asus dark hero board is a bit confusing for some in the Z790 chipset. if you have an M.two in slot one it will reduce the bandwidth in the PCie x16 slot two to 8x as a priority goes to the m.2. It will not do this in slot 1 of pcie x16. Unlike one of the MSI tomohawk boards will slow down pcie x16 in slot one if you put an nvme in slot one.

[@onoffgeorg9828]

its called m.2 fake garbage slot , a m.2 slot that slow down your gpu. thank you asus for the garbage dummy m.2 slot

[@tek_soup]

pcie 4.0 x8 is the same as pcie 3.0 x16 in terms of theoretical bandwidth. im running a 4090 at x8 and it is fine. my board knocks out the m.2_1 because i have to use the bottom pcie x16_2 because i have a watercooled gpu, that won't fit in the first slot.

[@scottcampbell2707]

Also, it is worth checking whether your GPU can use 16 lanes. Some GPUs are wired for x8 and would gain no benefit from a x16 slot over a x8 one.

[@zbigniewkrajewski7536]

Very good and informative, now please compare speeds of gpu going in x16 and x8. Thanks for very good video!

[@drxpsaucx4157]

There currently is no PCIE 5.0 GPU's 5 x8 is equal to 4 x16

[@Imgema]

I'm confused. You say that the Z970 boards have this issue and at the end of the video you say they don't. So which is it? I have a Gigabyte Z790 UD AX... Which slot should i use for this?

[@techluvin7691]

Very little in the way of a performance loss going from x16 to x8 mainly because graphics cards currently cannot saturate the bus.

[@jandras1]

Yeah, there are many other commentators who say there is zero reason to care about dropping GPU-dedicated lanes from x16 Gen5 lanes to x8 Gen5 lanes because we are years away from graphic cards that need more than x8 lanes or, equivalently speaking, will benefit from x16 lanes. If true, then connect your Gen5 SSD to the top slot, drop the GPU from x16 to x8, and move on with no reduction in GPU throughput.

[@tanmayhembram9249]

Excellent topic to discuss keep it up. Learned a lot.

[@theduck001]

What do you think is faster for the games data installation ? An 2TB M.2 drive encrypted with Bitlocker that is connected directly to the CPU with its x4 lane (as C: main drive). Or the games data on a second 2TB M.2 drive that is not bitlocker encrypted and not connected directly to the CPU with the lane, but via x4 to the chipset ?

[@steffenlze0178]

a bit of a problem? well, if i use the first m2 slot on my z690 Strix F then i have occasional stutters and laggs in games and often on desktop stuff. my 12600kf should be strong enough to handle a 4060, a 970 evo plus w11 and 980 pro game drive. the 4060 is pcie 4.0 8x by design so it should work but it doesn't. so i have to use the 3 m2 slots coming from the z690 chipset to have a decent experience.

[@acidmexx]

U enlightend me :D ... im a 1981 .... and i was like building 486 Systems, going to MMX166 and such :D ... there was no need to think about PCIe lanes at all :D ... Today im going to build a whole new Unraid beast and my "Mainframe" RenderPC ... and damn ... as i looked and benchmarked a lot of Mainboards and their diagrams .... seems like in 2024 its all about Lanes ... Thanks for that Video .... :) And even if you made a mistake about AMDs PCIe Lanes - - who cares - dual XEONs do their job pretty well .. tho the Threadrippers are insane :)

[@PaulMrPKcom]

Thanks, great info. I'm trying to decide which Z790 mainboard to get for my new pc... still confused. Looking at gigabyte-z790-aorus-elite-x block diagram. Look slike there is one PCI 5 x16 + 1 M.2 gen 4 connected to CPU, all other M2 etc are connected to the chipset. Shoudl I use the VGA + M2 connected to CPU or better to use M2 via chipset ? Maybe some one can recommend some mainboards that are better choice... ? Without breaking the bank :)

[@peterfalkner4436]

Check your manual if it indicates PCIEX16 G5 X16 AND M.2 X4 connected to CPU, then you will get the full 16 lanes for your GPU if you connect your M.2 to the top slot

[@kyrgeorge]

So what mainboard did you chose?

[@PaulMrPKcom]

@@kyrgeorge Gigabyte Auros Elite X wifi7 with g.skill ram @6000hz. Just had it few days, so far installed Linux without issues beside no wifi7. Win 11 works fine when installing using their media creation tool (not stand alone ISO), no M2 drives found, can't add mb drivers... The mb feels great, heavy and high quality, should last for next 5 years or so. On papper this new pc is 2.5x faster than my old pc with, but in reality for every day tasks the speed is about same to be honest. :)

[@OnBakePlatinum]

I wonder if the rtx 5000 series will be gen 5. Maybe by then motherboards will support gen 5 m2 and not sacrifice gpu lanes at the same time

[@RickyBobby_USA]

7:00 When is the gen 5 Wrx80 and gen 5 Threadripper Pro going to come out...I know it's coming...lol.

[@adensmith8553]

The kid video bomb is funny 15:11, great video super helpful even a year later.

[@MOSMASTERING]

I have been wrestling with my RAID0 ssd setup for 2 weeks now.. I dont have a GPU, im running a workstation. On an Asus Crosshair Hero x870e board, Ive got 2x MP700 Pro SSDs and I cant get higher than 14GB/s read speed which is half the theoretical max speed... I dont know why Im not getting the right throughput. I only have 2 PCIe devices, both M.2 drives that should be working together. There must be something wrong with my config. But Ive tried all the BIOS PCIe bifurcation settings and trying to force GEN 5 mode. Nothing changes the result or makes a difference.

[@chrisenoiu]

My new mobo has a diagram that shows 16+4 or 8x2 + 4 . It's important to know that because not all the mobos are cutting the 16 PCIe slot in half while adding a M.2 SSD on the top.

[@Hyperion1722]

With NVME drives getting cheaper, drive expansions is ideal for AM5 X670 chipset. I have a chugging Z170X motherboard but ok with me as I can directly install two NVME drives plus two SATA drives. The 4 sata ports were disabled when using the second NVME drive but ok with me.

[@SansP3ur]

Pardon my noobishness but how is it possible for four M.2 cards (in the Asus daughterboard) use the full x16 bandwidth for each card? If the slot is x16 and each M.2 fires at full capacity wouldn't they be choked to x4 performance because they're sharing a single slot? Otherwise the slot would have to be x64. I'm not a builder so this is purely inquisitive.

[@OutLanderUSN]

Each M.2 slot on the daughterboard has 4 dedicated PCIE lanes going to it, and those 4 correspond to 4 in the motherboard slot. If I'm remembering what I read about it a while back correctly. I think you also have to set PCIE bifurcation for the slot in the BIOS, but I could be mistaken about that.

[@jozsiolah1435]

On some Intel processors, the difference needs a better camera, I counted 5-10 more connections on the 2 ghz core 2 duo 667, 2 mb cache laptop cpu, compared to the pentium 2.2, 800 mhz fsb, 1 mb cache.

[@danielabbott9312]

For gaming a monitor will only use 4 lanes, I have a 13900k with a msi z790 ace, I have 3 monitors with 1 being ran on the igpu in the cpu and the other 2 on my 4080, I also have a gen 5 ssd, my gpu runs on 8 lanes because of this, but I have zero loss in gaming performance because 8 lanes is all the 2 monitors need

[@pcartisan2721]

Good stuff!

[@user-cw3nb8rc9e]

16:39 no more than 2 or 3 gpu cards will fit there, not 6 or 8.

[@taomahNEGEV]

I still do not know which the best slot is for the m.2 SSD for the system.

[@johnscaramis2515]

2:40 that's not entirely correct Ryzen7000 CPUs have 28 PCIe lanes. 16 for the PEG slot, 4 for NVMe, 4 for either a 2nd NVMe or for e.g. a USB4 chip and 4 lanes to the chipset

[@carlblavius9256]

Whats with the annoying background music

[@RobertBrown-fy3ej]

I agree to some extent BUT doesn't the connection between CPU and GPU separate on x8 DMI 4.0 which if I read it right is a different lane to PCIe 4.0

[@dismuter_yt]

Yes the Intel 1700 platform has x8 DMI 4.0, which is equivalent to x8 PCIe 4.0. That's double what the AM5 platform provides, and makes the Intel platform better on the I/O side, because reducing the chipset bottleneck is much more valuable.

[@RobertBrown-fy3ej]

@@dismuter_yt My thinking was that my Gigabyte Z790 MB has 5 NVME PCIe drives installed with boot drive in top most CPU slot separate from the other 4 (one in the PCIe 4.0 slot on an adapter) in raid 5. Thus the x8 DMI 4.0 is separate to any of the PCIe channels. as it works fine. The CPU PCIe lanes are 16 at PCIe 5.0 (GPU) and an additional PCIe 4.0 x 4 (top slot).

[@glennquagmire3258]

So if you did dual FPUcards that were connected together, I assume each would get 8 lanes as you explain and its total throughput would be hampered in tests like Cinebench, but the raw GPU power that both generate would be evident in some tests, but not others compared with a single GPU getting to use all 16 lanes.

[@ChristVill45]

I'm Very Glad that i Subscribed to you and didn't regret it. Every Videos you Upload always gives me Fresh Knowledge, Every small Information about PC components🔥🔥 I can Consider myself as a Computer Nerd🤓

[@ultrapeachykeenmonster]

been an intel fanboy for awhile, but this information is making me reconsider my next build. seems like amd/ryzen is the winner. whats the point in buying an intel platform now?

[@dizzywow]

AMD is not the winner. Intel provides 16 lanes to the video card and 4 lanes to the M.2.

[@diazjulianms]

Okay I get it now but three question, first question is does Integrated GPU use the PCIe lanes too despite being located in the same die as the CPU? and second question is does Laptop/Handheld PC Gaming motherboard (PCB) also have the chipset in Desktop motherboard or not? third question is does Laptop with DISCRETE GPU use PCIe lanes too? I’m genuinely asking because I know the answer for the first question (not really sure about the second one) but I just wanna BE CLEAR about it so please BE NICE all 😁

[@diosyntaxa]

Not sure about my new motherboard (still waiting on the system), it's a TUF Gaming B650 (plus WIFI which I got because X670 is simply overkill for my needs), it has three M.2s-lots and from what i can tell first two are fine to use but if I use the third one I lose access to the second PCIex16-slot (which runs at x4 I think). Since I'm only using one GPU I should be fine. Using an old GPU and will only use a PCIe4-M.2. though I could plug a PCIE5 one in since the first slot is PCIe5. Will use all three slots since I'll transfer the two M.2 I use in my current system... Yes, Threadripper takes it to another level, including another level of pricing :D Will probably never have one :)

[@thonymzb]

Thanks for the video! Does this lane switching also hapenns on pcie 4.0 / pcie 4.0?

[@peterfalkner4436]

The Rog strix Z690 gamming F has 1x pciex16 G5 and 1x M.2 x4, so you still get 16 pcie lanes for your GPU if you plug your M.2 in the top slot.

[@xBINARYGODx]

all z690 and z790 do this - the only time it matters for the top slot is later when gen 5 NVMe's come out - but given they still have no saturated, or otherwise maxed the gen 4 NVMe's yet, I dont think it really matters.

[@VndNvwYvvSvv]

What's funny is that half lanes is still more than enough on PCIE 5 and often enough on 4. Even the 4090 can't saturate the last gen bus. But we've known this is the case since PCI Express 2 first came out, and it's a great thing.

[@ArunSingh-rr8fc]

Someone below a month ago stated a 5-10% performance hit on the GPU at half lane/8x. That might be for gen 4 but I'm looking to future proof the GPU lane at 16x and stick with Gen 4 m.2 to the CPU.

[@leenagle2903]

Pcie Bifurcation. Not switching.

[@MuahMan]

All I know is that when I put my high speed NVME Gen 4 drive into that top M2 slot (M2A_CPU) that it drops my GPU to X8 from X16. How do I stop that!?!?! :(

[@jb678901]

One of the reasons why I still like my cheap X99 build (X99TF motherboard) with the XEON E5-2696v3 (18core/36 thread; 3.8Ghz turboboost). FORTY (40) PCIE lanes (albeit Gen 3)! I also like its FOUR(4) CHANNEL MEMORY and ability to support either DDR3 or DDR4 (limited to 2133Mhz, but in four channel)! Sure, it's a decade old processor. But at only $45, it can still deliver a CB R23 multi score of 14,050 pts. Yes...the IPC isn't great...and its efficiency cannot compare with modern CPU architecture. But it gets the job done well and it runs cool on air...and never exceeds 53C at 20C ambient. For gaming, it will typically run ~3.7 Ghz all core (turbo unlocked). On full stress loads, the 145W TDP becomes its hard limit and it will revert to 2.8Ghz all core. Mine is well matched with the venerable RTX 2080Ti.

[@cinemaipswich4636]

The PLX and PCX chipsets manage the use of all the lanes. Remember, USB, Network, Audio, etc need connections.

[@jabezhane]

Ha! Shouldnt really be an issue now in 2023 but if I use the M.2 on my old X99 board I lose a slot...totally, even though I have a 40 lanes chip. If I use another slot I lose my USB3.1 sockets.

[@Nalianna]

I just wish that more manufacturers would display on their websites if their motherboard supports pcie bifurcation (to x4x4x4x4).

[@thomasenright5282]

In order to get the manual you have to purchase the motherboard, all I want to know which motherboards to avoid that will cause this problem by dropping down your GPU down from 16 to 8, I want to avoid getting these motherboards. I don't mind which ever motherboard I have to use that won't cause this problem.

[@deepak_nigwal]

Most motherboards stopped giving the manuals with them already.

[@brettpureveen]

If you have an Asus z790 ProArt Creator board, and use the first 2 M.2 slots, do you lose any speed? Have a RTX 4090 in first PCIe slot., Using 14900KF processor

[@anonymous4gent]

I wanna play Sims 3 on the threadripper. Will I get 60fps?

[@tejiriamrasa3258]

🤦

[@oscarmetal]

You are not the troll we wanted but the troll we needed

[@inachu]

12:16 Worst designed motherboard ever. What is the best Intel i9 motherboard? Or do you prefer we buy the ASUS Pro WS WRX80E-SAGE SE WiFi II AMD WRX80 Ryzen™ Threadripper™ PRO Extended-ATX Workstation Motherboard ??? I just might buy it 🙂

[@GONZALOARTECHE]

I have a new ASUS ROG Maximus Z790 Dark Hero (WiFi 7) LGA 1700, and I buy also a RTX 4090 and 1 Crucial T700 2TB Gen5 NVMe M.2 SSD where I can place the M2 to be same speed and don't loose and PCI lane?

[@digitalQ33]

You can’t. I am building a similar setup with that board now, went with gen 4 ssd’s populating m.2 socket 2 & 3, the dark hero board both m2 socket 1 & 2 route through the cpu, but only m2 socket 1 is capable of gen 5, which will cut your 4090 to gen 4 x8 I don’t “think” you can run a gen 5 SSD anywhere but m2 socket 1. Love to hear others thoughts

[@dawbra]

Did you have simillar video about ram and what means 1:1 speed ratio etc and how to setup it?

[@godnamedtay]

Man, how nice is must be to be sponsored by AMD Threadripper…Jesus Christ.

[@essentialone1]

IVE ALWAYS UNDERSTOOD THE THE M.2 ABOVE GPU SHARES PCIE LANES AND BANDWITH WITH CPU WHICH IS THE FASTES AND BEST W2AY AS IN PERFORMANCE TO USE FOR YOU (OS) ETC AND THE OTHER M.2 SHARES LANES WITH SOUTHBRIDGE CHIPSET DEPENDING ON GEN OF MOBO AND CPU

[@deanpartridge9545]

I just built my son a 7800x3d rig using rog strix b650 e-e. It has 2 gen 5 m.2 slots top one under cpu I use. But the bottom gen 5 slot says in Manuel that if I use that it half's bandwidth to gpu 😢. I ended up using top slot then one of the gen 4 slots

[@st4849]

My MSI Z790 Edge WiFi DDR4 seems to have independent PCIe 5.0x16 + NVME 4.0x4 to the CPU and don't affect each other. Also, it says DMI x8 between CPU and chipset. Maybe this is how it frees up 4 PCIe lanes for the independent NVME slot?