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Sense check - G4 transplant
Posted by: croissantking on 2025-04-26 14:53:51
Hoping to get a quick sense check before I carry out a brain transplant.

I’ve got this 7400 466MHz CPU card and from reading around the forums I understand that it’s a straight swap onto a 750L CPU card. And furthermore that no voltage adjustment is necessary since both use 2.0V.

IMG_3828.jpeg

I’ll be using .78mm solder balls so the chip will of course sit lower down, will the heatsink need some kind of copper or aluminium shim to make up the gap, or can I just bend the clip to compensate?

Of course I plan to move the cache chips over. They’re rated to 250MHz, which is nice.

Finally is there any risk of melting the plastic on the underside of the ZIF when I use the IR preheater?
Posted by: Durosity on 2025-04-27 10:53:29
I can't offer any input on the pitfalls of doing this, but I'm excited to see the results.
Posted by: Daniël on 2025-04-27 11:09:46
Should work fine, the 7400 supports 3.3V L2 cache which I think this card uses.
The 7410 is what you can't use in that case, as while it'll actually work, it'll be L2 cacheless as this cooks the L2 controller in the die.
Posted by: croissantking on 2025-04-27 13:12:47
Yeah, I read about the 7410 cache issues on here, which is why I went for this 7400.

Hoping it will run at 500 or even 533 without issues.
Posted by: croissantking on 2025-04-28 12:09:49
I can't offer any input on the pitfalls of doing this, but I'm excited to see the results.
I’m not the first to do it, based on others’ success here it’s likely to work.
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