LC 475 - swapped in full 68040

[amatecha]

Successfully swapped in a full 68040 into my "new" LC 475 last night. It's a 33mhz '040 from my parents' old Quadra 950. No, sorry, it's not available - they only kept the motherboard which thankfully still had the CPU and all of the RAM on it! Anyway, I haven't yet done the resistor-swap to boost the speed to the proper 33mhz this CPU offers, but it should be a fairly straightforward task.



Probably the easiest upgrade ever.

I did find that the metal clips that hold down the heatsink do not have anything to "grab onto"... however I just squished the metal tabs inward more so they grab onto the side of the CPU socket a bit, to hold it in place. Works just fine. The heatsink is a bit heavy anyways and with the minor friction of the metal clips, it seems it should hold just fine as long as the computer isn't thrown around Later on I'll probably try to track down some type of adhesive thermal paste (if such a thing exists) to keep the heatsink on more securely.

So far the machine has 20mb of RAM total (4mb onboard + 16mb SIMM i found in an old Performa 6200CD I got from a thrift shop for $4....) Not too bad for a simple little machine, hey? I'll probably keep System 7.5.3 on it even though I feel inclined to run System 7.1 just for the improved performance. Probably no need though, now!! haha

 

[Byrd]

Later on I'll probably try to track down some type of adhesive thermal paste.

It most certainly does! But you don't need it.

1. Apply standard thermal paste to heatsink (thin layer)

2. Wipe away two corners

3. Dab on a tiny blobo of superglue/CA glue

4. Quickly apply heatsink to CPU

 

[amatecha]

true, I was actually thinking of doing exactly that. I already have some nice thermal paste from building PCs at work, and well, who doesn't have epoxy? Although, I wonder if the CPU heat would deteriorate it at all??

 

[Solvalou]

Do not use super glue on the CPU! Just stick to themal adhesive, thats mroe then enough to keep a heatsink on. I got an RC revision 25Mhz CPU on my Performa 475 and that's been held on for years.

Keep us posted on your 33Mhz mod, I would love to see how it is done, I might try it myself if I ever have a spare CPU (maybe even 40Mhz!).

 

[ClassicHasClass]

I'd be interested too. My NetBSD Q605 would definitely benefit from a little boost.

 

[Trash80toHP_Mini]

I'd like to see this too, as I've had the heatsink equipped 'o40/33MHz proc from my Radius Rocket in my Q605 for many years.

 

[techknight]

ive got a roll of thermal adhesive stickers, that i use for situations like that. The original intended purpose was for non-heatsinked LCD TV CPUs that would get hot and freeze up the picture.

Small northbridge heatsink, plus the thermal tape, and bingo. never have an issue again.