Overclocking this Mac to the limit using scrap parts and period correct mods

[@dstarling61]

I had a Centris 610 back in the day. I upgraded the CPU, with the Sonnet Quad Doubler. It made a big improvement. That Mac was followed by a G4, a G5, an Intel Mini and now a M2 Pro Mini. 30 years of Mac history!

[@acidhelm]

The 565 color format uses 6 bits for green. Our eyes are most sensitive to the green part of the spectrum, so it made sense to give green the additional color info.

[@jacobmckenna8661]

Time travel?

[@der.Schtefan]

​@@jacobmckenna8661Patreons get early release videos. KZbin displays the video publishing date when it went public, not when it was available for people with the secret link.

[@c1ph3rpunk]

@@jacobmckenna8661Patreon subs get early access.

[@DarkKnight32768]

Those computers used RGB 5-5-5 with 1 bit of padding in 16 bit (“thousands of colors”) modes. However, other standards and video hardware could use 5-6-5. On PC, ATi mach cards even offered both 5-5-5 and 5-6-5 sets of video modes. Might look like an oddity today, but at the time something captured by a camera or rendered that was not a high contrast full range picture, something that had large areas of similar tint, most often resulted in puke colors and banding when seen in HiColor mode. That extra color bit could be an improvement in those cases. Note that system interface and website graphics shown in the video stick to 256 color images, the default of that era, and thus don't change noticeably from switching to 16 bit mode and back. On the other hand, in software each color channel in QuckDraw is represented by a 16 bit fixed point value, which is way too future-proof. Maybe their intent was to make everyone handle color conversions in the most correct way possible.

[@Stoney3K]

@rommix0Sync on green only refers to the H/V sync signal being superimposed on the green analog video signal, so you don't need separate horizontal and vertical sync lines. It was a common way of sending sync on older video systems.

[@Darxide23]

Overclocking is a strange, inexact science. As you increase the overclock, you'll eventually hit instability where the system fails to POST or crashes shortly after, but sometimes if you continue to push the overclock you may hit an island of stability where it works just fine. This is true with these old machines and still applies to modern systems as well.

[@Col_Panic]

Yup! Very much a trial & error whilst crossing your fingers and being at it MUCH longer than expected, activity. I rarely do it anymore, but I used to a lot a while back (1995-2009). I was a teenager, then poor....then had a kid, making ME even poorer(harder to justify spending money on stuff like gaming PC hardware). Luckily, I enjoy trying to make older hardware run as well as it possibly can since for a long time I had not choice during the long periods of time between builds. Especially since when I did build, I could usually only afford hardware that was just made "last gen" giving it less longevity at least for gaming. In 2005-06 as PCIE GPUs were coming out, I was looking to upgrade, but didn't have enough money available (with kid on the way) for a full build. I ended up going for the best CPU my mobo would take (Athlon 64) cheap used, and the best AGP GPU I could (ATI x850 ALLinWonder), and some parts for a liquid cooling loop. I cooled the CPU and the GPU via Thermaltake water blocks and an old dirt bike radiator inside an old mini freezer. I spent about 3 months messing around with settings on the hardware and cooling system to get it stable. Once I did, I was able to play Oblivion with some pretty nice settings. Not as well as I could have with a PCIE card and newer CPU. I ended up having to dig up my key gen for XP Pro so I could use more RAM, too. That was actually the last upgrade for me until like 2009ish. Unfortunately I fell for Nvidia Marketing. It was when they released their first card series with DX10. I always used ATI (AMD) after a bad Nvidia experience early on. Unfortunately having had such a long time between builds, I was worried I would shoot myself in the foot if I didn't get the DX10 card even though the AMD version was a much better value(some things don't change). I gave in and quickly regretted it. The card was a glitchy mess way overpriced. The worst thing about it all was that when I finally upgraded to my first full new build in a while years later, there were still hardly ANY games (at least ones worth playing) that even used DX10. I learned a lot from all of that at least. Mainly that it is almost never worth adopting the newest hardware right away since almost nothing will make use of it until it has been on the market long enough for devs to take advantage of it. Also, it often changed before then too! By the time DX10 games were regularly released, DX10 was quite different than the version that was first released by Nvidia. That happened again with my RX480 later on with DX12. However, I didn't buy it because it was an early DX12 card and it just happend to be a feature. Nvidia was really hyping I though. I think AMD prob only included it to avoid customers making that choice I did with the DX10 card. That was a great card though and the driver updates actually had it working quite well with DX12 even as recently as a 19 months or so. Back to overclocking, I replaced the rx480 with a Sapphire 6900XT Toxic (extreme edition) with integrated AIO liquid cooling and a 360mm(3 fan) radiator. Although, I didn't OC it, it was already done for me. It is prob the best GPU from that run except maybe the 6950xt version of that card which was not available when I got mine for an awesome price(at the time). It's a fantastic card! Especially with my 5800x3D. Anyway, that concludes this overlooking story. Overclocking has its place, but unless it's done for fun(to see if you can) there really isn't much incentive now days. Most CPUs come pushed about as far as they can be while remaining stable. Plus most CPUs on the market are already overkill for most applications unless you get a crazy expensive card like a 4090 or something and are trying to play at 4k with over 60 FPS full blast. Still, once you buy what you would need to OC a new chip enough to be worth it, you might as well just buy the better CPU. Heck, my "last Gen" AM4, 5800x3D ties or beats the 13k & 14k(aka 13k) intels that are nearly 3x the price in gaming. Ok now I'm done! $ end /rambling commrant\:

[@hp4985]

I'm pretty sure there's an equation for this I forgot what it's called but it's related to the mandelbrot set

[@Wtfinc]

@@hp4985yeah, there would be but you would have to know things you likely wont have the data for. Actually, what likely causes instability is by raising the voltage will change the bias of the transistors and if the bias gets to saturation then… ya know. And speed will have to do with capacitance and inductance. Too fast and the signal will become a blur. You also have diode breakdown voltage. So if you have a formula for all this, good on ya. Lol but its not worth much except for having some fun with math. You may as well experiment. Now it could be useful if ur chip is super super expensive.

[@Rroff2]

Depending on how you are overclocking this can be due to various bus or clock straps/ratios - they'll often have a certain number of multipliers relative to the CPU frequency and as the CPU frequency increases after a bit they reset back to the lowest ratio then start increasing again (grossly simplified).

[@itsjustrobby]

100% evergreen comment there!

[@willproctor7301]

The memory usage reminds me of my beloved Risc PC on RISC OS. Same limitations with the VRAM. Nice upload :)

[@RickThornquist]

I'm always learning new things from Adrian's videos - I had no idea about needing a managed switch for my old machines. Great stuff.

[@adriansdigitalbasement]

They are so cheap now as well ... so just setup some ports for 10/half duplex and you won't ever have issues with the ancient machines.

[@c1ph3rpunk]

One to remember, at 10M half-duplex collisions will be normal on that wire, just not excessive ones. It’ll actually be doing CSMAD as designed. To a point.

[@benjaminrondeau3148]

You can also avoid having to configure anything for your older systems by plugging them into an unmanaged NETGEAR GS305v3 switch before going to your regular router. It works perfectly well with older Macs and PCs with 10Mbps half-duplex Ethernet as well as strange early 100 MBps cards while segregating them and their quirkiness from the rest of your LAN.

[@Cherijo78]

The other reason to use managed switches, or at least partially managed smart switches (which can be cheaper), is to use VLANs to separate out these older machines with vulnerabilities and odd behavior from the rest of the modern computers on a home network. I also put an older B or G level router on the same VLAN so it's isolated given the known vulnerabilities in these older routers that might only have WEP or WPA1. This is one part of my strategy to manage older machines, including running Win98/XP/7/etc for safety.

[@slightlyevolved]

​@@Cherijo78Just a heads up, most of those cheap managed switches don't support VLAN, or at least not in hardware. Probably wouldn't matter for these old machines, but I'd pop for a Mikrotik hEX or hAP ac2 for full manged and VLAN hardware support. As a bonus, something like the hAP ac2 can even be used as a switch to wireless bridge so you can connect these machines to a WiFi network.

[@tubejay1]

Oh man, that old netscape load screen brings back memories!

[@shmehfleh3115]

On SMD resistors, '100' means 10 ohms with no (zero) multiplier. A 100 ohm resistor would read '101', or 10 ohms with a single 10x multiplier.

[@kargaroc386]

Like a decimal floating point format.

[@HalianTheProtogen]

10×10¹ Ω ;)

[@waxore1142]

That is officially the first time in my life I've ever seen a computer overclocked making a visible difference in normal use. I can now die happy...

[@soullessneutral8226]

idk why but i find modern gifs being rendered on older machines like this hilarious. Great video, and I learned a lot!

[@scarboroughyork]

Excellent video, loved the screen background colours too, as well as the indepth advice. A bit of a nostalgia hit from seeing the Netscape browser, and logo. I recall using video and audio calling with some Netscape app back in 1994/5 (PC). Love this Mac! good job.

[@Kenny_Powers]

I have an in-box Centris 610 overclocking kit from 1994 sold by KS Labs as the "Alacrity 610". It's similar to the RocketSocket pictured in your video in that it's a socket for a crystal oscillator that slips ontop of the computer's built-in oscillator. It also came with multiple crystal oscillators, a heatsink/fan, and an installation manual.

[@tw11tube]

@28:20 The original IBM PC/XT didn't just use that crystal for the CGA card, but as the primary clock source for the whole system. IBM was cost cutting the PC design at every corner possible, while still maintaining the sturdy business look of the case. The 14.318 clock signal is used to derive the 4.77MHz processor clock (/3), the 1.193MHz timer base clock (/12) and (as you already mentioned) the CGA pixel clock (1:1 in 640 pixel modes, /2 in 320 pixel modes). Those oscillators were produced in high volume (i.e. at low cost) already when IBM designed the PC, and by being part of the PC architecture, they got the industry standard frequency for cheap crystal oscillators later on. The original IBM PC in a standard configuration did have a second oscillator on the "monochrome display and printer adapter" (MDA/MDPA) at 16.257MHz a third one on the floppy controller (at 8MHz) and finally a fourth one on the serial interface card (1.8432 MHz), because those clocks couldn't be derived from the 14.318MHz reference. Note how all the options I mentioned were unnecessary if you used the originally intended "base configuration" of 16K RAM, no floppy drive, CGA card and a tape drive as BASIC program storage, running only ROM basic or games loaded from tape, so that kind of machine really fully ran of the one 14.318MHz clock. This configuration never hit the market (although IBM employees could get it), so I am unsure whether any IBM software was ever released on tape. The actual base config a normal consumer could get included 32K of RAM and a floppy drive. The IBM floppy boot process is incompatible with 16K machines. In PC evolution, the 14.318MHz clock stayed the "reference clock" for a very long time: Most PLL-based clock generator chips, at least up to the Pentium III generation (i.e. the end of the century) use a 14.318MHz clock input. Many clock synthesizers on Super VGA cards also use a 14.318MHz refence clock (although some VGA pixel clock synthesizers use a 40MHz reference clock, as 40MHz initially was a common SVGA memory clock when the split RAM/pixel clock designs started to appear - so a 40MHz clock needed to be provided on the SVGA chip anyhow).

[@ClayCowgill]

Coincidentally, I have a commercial overclocking add-on for the 610 (and similar) sitting right in front of me. 😆 It used a PLL block synthesizer and a sixteen position rotary switch to choose different clock speeds- there’s a little injection molded piece that just press-fits over the SMD crystal. Probably circa ~1996. If I recall correctly, some models of Mac (and OS) would notice the upgraded clock speeds and change their product names - e.g. Centris would become Quadra, etc.

[@somegreenguy]

i know for a fact they would do that with a powerpc upgrade too (ie a quadra 810 would become a powerpc 810)

[@tschak909]

@Adrian, it's called AAUI, "Apple AUI" Apple commissioned Amphenol for a custom connector, and paid for all the custom tooling and ordered a bazillion of them.

[@benjaminrondeau3148]

Fun fact, it also ended up on IBM's LAN Adapter/A Microchannel Ethernet adapter.

[@reddragon27284]

I think the third digit on SMD resistors is the same as colour codes on THT ones. So a 0 for the third digit means no zeros so that was a 10 ohm resistor. I’ve made that mistake before too.

[@CarputingYT]

What a very nice formatted video with a well spoken host, pleasure to watch this video and was entertained while learning along the way. Thank you.

[@johnsonlam]

Nothing fell better than making old things works better by modding with spare or scraps parts, thank you for your video.

[@SaraMorgan-ym6ue]

gives new meaning to the song push it to the limit🤣🤣🤣

[@schnuder]

I have fond memories of this computer as I was the system and network administrator for a computer lab of this and similar models in my high school as part of an “independent study” class in computers. This included upgrading from LocalTalk networking to Ethernet to connect to the school district’s first non-dialup internet connection, a leased 56k data line. I remember using crumpets to make all of the Ethernet cables ourselves to keep the cost down.

[@rivimey]

For me, a crumpet is a pancake-like food usually eaten with butter&jam... can you elaborate on what you used?

[@schnuder]

@@rivimey it’s an autocorrect error. Should have been “crimpers”. We used some creative methods to get things done with our limited budget but I don’t think we ever resorted to baked goods for anything other than our morale.

[@robinsutcliffe_video_art]

I love how enthusiastic and knowledgeable you are Adrian. Thanks for all the enjoyable content!

[@ModBay]

Always hard to leave something behind you love. Good luck in the future and best wish. Look forward to seeing more.

[@Morphling92]

Adrian you are so awesome. And you know all this knowledge and you present it well and cleanly. And it’s understandable. Thanks for a bunch of hours of great content and computer work!

[@Jibbertronics]

Hey Adrian, just letting you know that I think there is a slight typo on the on screen text at about 16:50 where you talk about the EC variant of the CPU. On the on-screen text you listed both the second and third variant as “LC”.

[@adriansdigitalbasement]

Ah well, oops. Thanks for pointing it out sadly no way to fix it now. (I'd have to take the video down)

[@Jibbertronics]

@@adriansdigitalbasement all good, great video. You have inspired me to try doing some similar mods on my C610! 🙌

[@stpworld]

Ive got an apple workgroup servre 60 and it makes the chime but then it does the crash up sound and I do not know what is wrong is there any thing you can help me to do to save it?@@adriansdigitalbasement

[@ZiggyAndTheSpiderFromMars]

Reminds me of the ancient days of overclocking my old Power PC 60 to 80mhz with a little piggyback clock crystal that sat over the original clock crystal. Really helped with Doom 2.

[@froller]

SMD resistor marked "100" is 10 Ohm, not 100 Ohm like you might think. Marking is XXY where XX is 2-digit value and Y is the power of 10. So 100 means 10 * (10 ^ 0) = 10 Ohm.

[@nepas3628]

nice video Adrian, congrats. btw I've heard that back in the day there was a battle among the users of 68040 Macs, 68040 Amigas and 486 PCs in regards which machine was faster (better). As you have all the machines there at the lab, it'd be nice to test who was right for once and for all. Maybe you could include the 68030 vs 386 either, just an idea. keep with the great content.

[@absalomdraconis]

It can be done, but depends on so many factors that it'll normally be better to treat it as program-specific rather than to treat it as a generic subject. For example, slightly more adventurous ISA bus hardware+driver combos could transfer most or all of their data movement to DMA channels, but less adventurous examples might implement all of that in software, leading to massive performance differences...

[@little_fluffy_clouds]

Faster at what exactly? Synthetic benchmarks such as MIPS and Dhrystones? Running specific apps or games? Certain Photoshop filters? Ray-tracing a given model in POVray? It’s tricky to compare performance of wildly different architectures. Depending on what you pick, you’ll find a different winner.

[@TomConder]

Man, this is great! Thank you for quality content.

[@ChairmanMeow1]

14:01 just seeing that logo again was so nostalgic. I probably saw that pop up window 10,000 times as a kid!!

[@user-tb5ns7hc5i]

Love that NEC monitor. Great video. Would have been great to do this back in the day but too cost prohibitive for damage and failure risk at the time.

[@chadhartsees]

This was fantastic. We forget about the speed of video memory/video cards, RAM, and CPU power when we look back on the old and slow dialup days.

[@chuckthetekkie]

I watched your 3rd channel video about surfing the internet like it's 1999 on this Mac. but you had comments turned off so I'm posting my comment here. I wish I had internet that was that fast in 1999. I was stuck with Dial-Up in 1999. We didn't get broadband until late 2008. Heck, we didn't get cable TV until then either.

[@BeyondDuctTapeFixItRight]

That was pure joy to watch you walk through this upgrade.

[@DuartJansen]

Lol, I don't have any old computer anymore, but found this highly entertaining! Thanks, I subbed!

[@MaddTheSane]

1:36 That's an AAUI port, for Apple AUI. They were present on pro Macs up until the Beige G3. Yes, the AAUI port shared life with the RJ-45 port. As an owner of a PM 7200, 7600, and a Beige G3 (also had a 7100) briefly.

[@mattpierce5009]

Awesome! I had a Power Mac 6100 back in my collecting days, with a little device called a Powerclip that, expectedly, clipped onto the top of the crystal that could literally dial in an overclock via potentiometer. Mac overclocking always felt kind of exciting and novel, coming from years of PC overclocking where you could just do it in BIOS :)

[@alligoodw]

I'm not a technical person, but I absolutely love your channel. It's fascinating and interesting.

[@djdoo]

Excellent work as always Adrian! I would do a couple of things more to this really neat system, -Retrobrite -Put the CD Rom sled and plate retrobrited there even without the cdrom drive -Put a 68040 full fledged cpu for having the maximum capabilities! -Find if it can take more VRam for higher resolutions with good colors now that the CPU runs 42% faster Kisses from Greece!

[@Kabelkerl]

So much Fun to watch you tinker with these Mac´s , in 68k Area i was using also a Amiga 2000 with an GVP Accelerator with an 040 with 33Mhz, Ram on Board and an SCSI Controller. After a while there was no Software anymore for the Amiga to play Sethlers 2 and Sim City 2000 i emulated a Mac with Shapeshifter. The Tinkering started later with me wenn i importetd Powermac´s frome the US and also overcklocked them wit Crystals and such.

[@wnblair]

Love seeing how much you can push a stock system to it's limits. Great video!

[@kirishima638]

I remember overclocking my LC475 from 25 to 33mhz by swapping some resistors. Made a big difference. Loved that computer.

[@AureliusR]

That doesn't make any sense. Swapping resistors wouldn't change the clock frequency. Unless it's using an RC oscillator which I strongly doubt.

[@devnull73]

for anyone wondering, "100" on an SMD resistor is 10 Ohms. As confusing as it is, you read it as "10 and 0 zeroes". So 100 Ohms would say "101".

[@SomewhatLazy]

I want an entire series where you max out computers with as many upgrades as they can take.

[@kevinwright7931]

With surface mounted resistors 100 = 10 ohms, 101 = 100 ohms. Separate the the first 2 digits from the third one. If third digit is a zero then drop it the resister is the value of the first 2 digits. if the third is 1 - 9 then it's 10 to the power of the third digit then that value times the first 2 digits. 104 = 100,000. the quick method is to add the number of zeros of third digit to the first two digits. If you want to put a 50 ohms resistor there use one marked 500.

[@tcscomment]

the 68LC040 is mentioned twice at 16:55, probably Adrian meant the 68EC040?

[@The.Orchard]

It's called AAUI (Apple AUI). You have a valid point about the DB-15 being the same as the display connector, but I strongly suspect the other motive for the smaller size port was to make it an easier fit on portables. Plus, since Apple had so many onboard ports on most Macs, there was a limited amount of space even on desktops -- indeed, even wide ones like the Centris form factor. The problem with the AAUI is that the squeeze-to-release design isn't particularly strong. Many, many times, we used to have LaserWriters fall off the network because someone would bump the AAUI connection while getting to the power switch, loading paper, or clearing a jam. I eventually started looping the short cord through one of the clips for the Centronics parallel port (which was conveniently next to the AAUI port), to help secure it, and they came loose less often, but it still happened.

[@jasmijndekkers]

Nice build Adrian. Greetings from Steven from the Netherlands

[@StrangelyIronic]

I've got an Apple IIGS and Macintosh iici that I go in the late 90s from my uncle that worked as the head tech person at a massive printing company that also did design work. Rescued from the closet/trash pallet a year apart and given to me when I was around 7 or 8 years old to learn programming with. When he had them ordered, money was a barrier, so he maxed them out with the best parts he could get at the time period wise over their use with expansion/accelerators. I still use both computers all the time making games, applications, and demos for fun. More the IIGS for its quirkiness, but I do love the iici too.

[@powerpower-rg7bk]

12:02 A bit of a correction here: each color channel is 5 bits for RGB plus a single bit for alpha on 68K Macs. Windows has a 5-6-5 arrangement for 16 bit color.

[@NoNameForNone]

If you want to know for sure if it's EDO and it's a 3.3V module and do not have a memory tester: get a ohm/signal meter and check if pin 66 is connected to VSS (aka ground, on pin 72). It's not 100% fool proof as some modules are mismatched but it's in spec for only EDO to have pin 66 connected to ground. On Fast page mode ram it should not be connected. This does NOT work for 5v modules.

[@adriansdigitalbasement]

Ah that's good -- I hadn't heard of that trick before. Nice! Yeah that Ram Tester is a rare thing to have -- so 99.9999% of people won't have the luxury of using it.

[@andyrecord]

In college (1996-ish) I had a 50Mhz replacement CPU with a heat sink and fan on it for my Quadra 605. It was from a compnay in Wichita Kansas. Can't remember what the name is/was, but it was a significant speed boost!

[@26DR715]

That's one of a hell upgrade we'll done Adrian

[@geoffpool7476]

Great Video! I love the steps and teaching presentation you use. Personally, I'm PPC G3 Mac person, but I do love all the old Apple products. Looking forward to the next video!

[@EvilTurkeySlices]

I’m open for nearly any Mac architecture. I only have Intel and PPC right now, but I want to get a 68k machine. MX is too expensive right now.

[@JapanPop]

Takes me back to my tech lab assistant days at university! Loved the Centris, and all the transceivers!

[@10p6]

Nice. Reminds me back in 1992 when I did a clock mod to run my Atari Falcon at 32 MHz over the standard 16 MHz. (I did add a 16 / 32 switch on mine too)

[@fepatton]

Those Mac's were insanely priced back in the day. When my kids were growing up in the '90s and '00s, I somehow managed to acquire a Centris (might have been a 610?) and a couple of Quadras from work. The kids happily used them to draw and to play Freddie Fish, Putt-Putt, Spy Fox, and other classics! We had them hooked up to printers and the internet, and they got everyone through elementary school. We all have a soft spot in our hearts for those pizza box Macs!

[@federalexpression]

I had a MacSE30 followed by a Quadra 650. Wish I still had the hardware lying around.

[@wotsac]

I've managed to get both of those for my collection. The Centris (same diff) 650 is one of the sweetest deals in 68k Macs.

[@zero0ryn]

That is awesome Adrian 😊

[@BasedBidoof]

Such a cool video. Being able to do the old school mods on the period hardware. I remember my dad telling me stories of crazy over clocking back then. I got a stable 4.5ghz on an fx8350. Tried to oc a 9600k after I finally upgraded, and it was so unstable. They just don't make em like they used to. Lol

[@thehighwayman78]

Cool I saw that jumper link coming off after you soldered the socket on. I was thinking at what point you would notice 😆

[@WelcomeToMarkintosh]

Nice! Well done-thanks for another great video!

[@ReinMixTape]

It's awesome seeing old mac being heavily upgraded.

[@RetroGamingWithEdgarRivera]

Ahh yess, I really love the idea of tinkering and using spare parts and period correct mods and pushing the Macintosh Centris 610 to it's higher power performance is delightful indeed, I really like that stuff.

[@CrowDazzle]

This was my first computer. I had to use a software FPU back then in order to run some of the plugins for Photoshop 2.0. I later upgraded to the standard 040 processor which had the FPU. I still have the original LC040 processor in a box. I seem to remember, at least in San Diego, the Centris 610 was less expensive than the Quadro 610. If the price was the same I would have gone with the Quadro but my dad was selling some company stock in order to buy this for me. I may still have some software from the era on an archive cd somewhere. I replaced this system with a Power Computing Power 100 clone.

[@micksam7]

You might want to consider trying your crystals vs the function gen with the faster processor. The long leads might cause issues.

[@Bushougoma]

2:26 Apple using proprietary connectors so they can sell the proprietary adapters at a high markup. Good thing they don't do that anymore lightning cable *cough* 😁.

[@dstarling61]

When Lightning first came out, it was way better than any other micro connector. It was years before USB-C finally caught up. So, I think it should get some slack.

[@questionablecommands9423]

Man, that old Netscape. I remember finding the animated logo files for when a page was loading and modifying them so my browser had a custom animation.

[@AureliusR]

It's crazy to think that the overclocked Centris 610 was getting 1.28 Dhrystones, which works out to a DMIPS/MHz of only 0.04! Whereas the microcontroller I'm currently using gets 1.22 DMIPS/MHz... so even at 2MHz it can beat the performance of the 68EC040 @ 32MHz. And at the normal clock speed for this micro (48MHz) it scores 58.56 Dhrystones! Shows how far we have come in pure efficiency of silicon.

[@HikikomoriDev]

That Centris looks absolutely beautiful coupled with that NEC display. Look at how beautiful the smooth flowing lines are through out the design language among the two things... The Macintosh is a little yellowed but imagine how amazing it would had looked when new coupled with the CRT. Very pleasing to look at. It's not an eye sore compared to today's custom machines which look like they come from the devil with those fan lights.

[@Dr_Mario2007]

PowerPC 603e and 604 got slightly better emulation performance as the problem was down to the size of the L1 cache RAM on-die (I think it originally was 8 KB), just to help the emulator performance a bit more.

[@GeoffSeeley]

Memory unlocked! Been a while since I've seen the flying toasters!

[@stazeII]

Greetings from Eugene! I Remember these old machines. Old Asante adapters. Lots of Marathon multiplayer lan parties. :) If I recall, the IIFX was an overclocked 40 series. Also used super weird ram (at the time) if I recall. Oh, no, it was a 30 series! That’s even weirder. lol.

[@horusfalcon]

I'm not a big Mac fan (and I won't bore you with why), but this mod was interesting nonetheless. For all you Mac fans out there, Adrian is keepin' it real for you. (Of course I gave the video a like! I'm not a fanatic or something worse... 😁)

[@ChannelSixONine]

I love it when you service the floppy drive~

[@mfryer100]

Very interesting video. Thanks for sharing.

[@soloflo]

Nice! System 7 always had a nice ring to it, marketingwise. I think it was the first time Apple really pushed marketing to highlight the OS launch.

[@tme2912]

On my Macintosh performa in 1995 I was connecting to BBS servers. not yet internet

[@techkev140]

Nice to see new life in older systems. Shame the plastics on the case parts don't hold up as well (colour wise) as the internal components. Keep up the good work. Already pointed out below but around about 16mins in... You listed the 68EC040 on the bottom of the list displayed, as a 68LC040. When you talking about versions of the 68040 without FPU and MMU.

[@IlBiggo]

Not just colour-wise. These machines often have plastic clips to keep things in place; in time, those plastic clips become so stiff that they break at a touch. Hurrah for 3D printers!

[@furbies]

Still have an AAUI to ethernet RJ45 dongle in my network cables box... I haven't got any macs that can use it now, but it is a blast from the past. And there's a few Appletalk dongle boxes there too...

[@phipli]

The resistor you put at R146 is a 10 ohm resistor, not 100. The last digit in the number is the number of zeros, so it is 10 x10^0, or 10 Ohm.

[@Redlynx_X]

I started my career as a graphic designer on one of these. So many memories, I wish the one I had back then was overclocked. :)

[@glonch]

Excellent work - bravo!

[@LeoBerardino]

Great video Adrian :)

[@twocvbloke]

Numbered resistors still catch me out, that one being 10 + 0, for 10 Ohm, where a 100 ohm woulf be 10 + 1 (which I managed to remember thanks to watching BigClive for many years now!), though colour-banded ones, yeah, I never managed to make the colour to numbers thing stick in my head... :P

[@clrlmiller]

That is called an “AAUI” port for Apple AUI. The reasoning was compatibility for an era that used 10-Base-T (RJ-45), 10-Base-2 (Coax cable with BNC) connections, or even Thick Ethernet. In 1994 there was often a mixed Ethernet environment with a server room using 10-Base-2 to save the expense of a hub for a small room where the systems were mere feet apart. The Server room would connect via a bridging hub that had both RJ-45 and BNC connections and that would connect to RJ-45 only hubs.

[@marcinmiklaszewski9336]

You convinced me. I'll overclock my LCII. It is sloooooow! I wish netscape was anything close to your original speed. But its an only mac I ever had. Motherboard has a place for plcc socket for fpu I think. I may just try installing it. Anyway it's my first mac and I was little disapointed by its performance. My first Amiga seems much more responsive but it is not 100% fixed yet. Thanks for what you do.

[@madigorfkgoogle9349]

unless your first Amiga was A3000 or A4000, then the LCII is way faster computer.

[@steveschein2619]

I've still got my Quadra 660AV I bought back in the day. It got me through EE school. I remember doing this exact same mod with it. Blazing speed from 25MHz to 33MHz! Still works to this day.

[@marcussteck3782]

as always.. nice work 👍

[@BrianClem]

If the world ever lost all digital knowledge at once, I vote for this guy to lead the Renaissance. Who else would know so much about electronics?

[@perinoid]

Just wondering... Would it start with a 68060 (via a power adapter like the ones used to upgrade 1240 cards to 1260 - Apollo for instance). Yes, I know, a 060 is not a "Mac way" 😉

[@JSMCPN]

Nope, the Apple ROM doesn't have the necessary code to support 060, even in 040 emulation mode

[@AlistairKiwi]

I wish I could have seen your video way back after I'd bought 3 or 4 pizza boxes - these wow the pizza box Macs. There was another Centris, I think, that had a higher speed. I had 4 of these 610s I seem to remember. Luckily, these were for employees and not me! Ugh, it was not a zippy computer. But, it was very dependable. Mac SE/30 - totally not clean ROMs, but we all salivated over them and wished we could have one. I was still forced to use my Mac Plus back in the SE/30 days. Omg, I remember using an Asante connector, and then having to use the old Internet explorers. They may have not all been Centris computers but also Quadra. Anyway, it was a huge investment meant for my company to buy these darn things. Quite honestly, considering I had to buy 25 Macs, these were outrageously expensive. I had to do it over time.well,over 18 months. My money, my pain.

[@davefiddes]

Did you mean to use a sine wave on your signal generator rather than a square wave? Those clock modules generate square waves. Maybe the PLL clock doubling circuit is not generating a stable clock.

[@jaycee1980]

good point, the original 10Mhz clock looked quite square.

[@Cyraxworg]

Awesome retro oc video! 🤩

[@PoLoMoTo2]

We often end up swapped SMD resistors for demonstrating different LED brightness's for marketing at my job among other things. The best way to do it is with hot tweezers but just doing a couple it's usually just easier to do it with the regular iron, or if it's in a place the hot tweezers can't get. The best way I've found is to remove all of the solder after removing the old resistor, then put solder on one pad, then position the resistor on the board next to it so you can heat up the solder and just slide the resistor into it and then just solder the other pad. Seems to give pretty consistently nice results, definitely easier than hot air IMO if that's your only other option.

[@apocalypsevingt-cinq156]

What a nice trip to my younger time.

[@thenerd6192]

Between this and Action Retro’s video earlier it seems that everyone is overclocking their vintage Macs today!

[@one_b]

We had these 610s in our classrooms in Junior High. (And later 6100s with PowerPC and a cdrom... I think?) Those of us who were into computers quickly figured out how to by pass the "FoolProof" security suite, copy all the school's software for home, and wreak all kinds of havoc in the school on the network. >:) The teachers were completely useless when it came to actually using any computer so they never thought twice about us constantly rebooting the machines because Netscape was such a completely unstable mess to use. One day the vice principal busted into our classroom demanding to know who had been printing silly chain letters to all the printers around the campus during our free period. The other guys and I had already put the printers back to the default for our room, relocked the machine, and rebooted, and calmly continued our poker game at our desks. Ah the good old days.

[@benotsilent6703]

35:00 such a cool use of a modern tool to generate a variable clock rate. Imagine if you could vary it similar to a modern cpu for power saving.

[@sammacomber8769]

I had 128megs in my IIci, upgraded that thing like crazy. Had a turbo 601/66, rasterops 24bit video/capture card, PAS-16 16bit sound card, and an FWB fast scsi card with an external RAID.

[@xnonsuchx]

I got a Centris 650 some time ago (still disassembled and unknown if working…but Maxell battery removed!) and all the info I found on overclocking with crystal only reliably works up to 28-30MHz. So I’ve been occasionally looking online for one of the more advanced 40MHz+ accelerators. And yeah, those older chips could really handle overclocking. I know there were a lot of 8MHz 68000s running at 12 or even 16MHz and the Atari/Amiga 060 accelerators could often get 80-100MHz out of 50MHz rated chips.

[@stevenclark2188]

It looks like the signal generator is set to sine waves instead of square. If that's the case could the long rise time be causing stability issues?

[@Scruit]

I also use another feature of the manages switch for my retro computers - VLANs. I have a retro computer VLAN that has firewall rules that can only access limited things, like my NAS (via ftp) and my centos8 ssh jumphost. This prevents the older vulnerable computers with known vulnerabilities from the unwashed internet, but I can still download stuff from the internet if needed.