LC575 68LC040 - CPU info?

[phreakindee]

Coming to you from my "new" LC575 here :beige: ... and I see in the System Profiler that I have a 68LC040 and I was wondering if all it would take to move to a full '040 is a CPU swap? That seems to be the concensus online, but just wanted to make sure it was that simple.

Also, "thousands of colors" is an option under Monitors so I am assuming that it already has 1MB VRAM installed and wouldn't need to bother with that.

Thanks guys

 

[equill]

Certainly the MC68040 and MC68LC040 members of the 68040 family are pin-compatible. Most MLBs will accept and use the FPU, but a few 68040 accelerator cards may need jumper changes and ROM updates.

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[phreakindee]

Yeah, that's one of the things I was wondering about... the LC575 seemed to be rather straightforward, as far as you just drop in a 68040 and you're okay, no need for any further cards or switches.

 

[LCGuy]

That is correct. In fact, I have a similar machine to you (LC475, uses a very similar mobo design to the LC575, but in the "pizza box" case), and have done exactly that! All I did was pop out the old 68LC040, pop in the new 60840, flipped the switch, and I was off and away.

 

[phreakindee]

All I did was pop out the old 68LC040, pop in the new 60840, flipped the switch, and I was off and away.

Awesome then, exactly what I wanted to know thanks

 

[porter]

Did same for Quadra 605. Complete success.

 

[Quadraman]

I did the swap in a Performa 631 and it worked fine. Just be sure the 040 is rated at the same speed or higher than the LC you are replacing otherwise you will be overclocking the 040 and it may not stand up to it for long considering the age of any remaining 040 chips. The pathways inside the chips still deteriorate over time even when they are not in use, so overclocking is more likely to create short circuits in older chips.

 

[register]

Be careful not to bend the pins when replacing the cpu. Get a passive heatsink using the whole area of the ceramics, fit it in place with some thermal conductive but electric insolating compound. The heatsink should be fixed with some sort of clamp, too. In case you have got a 40 MHz rated 68040 or you do not mind to overclock, look at the following thread as well: Price Drops on Mac goodies for sale... plus free disks!, where TylerEss and DavidB kindly adverted to instructions about overclocking the LC 575.

 

[phreakindee]

Found a 33mhz 68040 in Great Britain via eBay, typing this on my newly-upgraded 575! I will say, that was the easiest and hardest CPU installation I have ever done! Easy in the sense that literally all you do is lift it out... hardest in the sense that it is the tightest-fitting thing ever made.

Any fellow n00b who wants to do this who may read this: don't be shy with it! You will have to tug on it a bit, and push even harder to get the new CPU in.

Be extra sure when removing to do it SLOWLY, working from near the corners on either side. This will ensure one side doesn't pop out before the other, bending pins.

Is this upgrade worth it? I'd say so, yes. Wolfenstein 3D runs noticeably better and is quite playable, and everything graphic-intensive has a bit more speed which is great. Flying Toasters from After Dark 4.0 now flies along quite nicely! [] ]'>