Yeah; thanks. I found this site a bit ago and was originally looking for the 'cross-reference' between Apples catalog number (M4849LL/A) and the actual part number on the chip. I finally discovered that it was 820-0754-A. If anyone rummaging through their parts drawer stumbles on one of these please let me know as it would save me a bit of trouble.
Do you happen to recall which Mac(s) used this method?
One thing that gives me hope is that the older revisions of this motherboard explicitly say "ROM/Cache" next to that socket. The revision of the 5260 has the word "ROM" removed. It only says "Cache." Of course the Apple documents that reference this machine use identical diagrams (even the website above does) and leave the "ROM" phrase there. That makes sense of course since the boards are pretty much the same except for a few revised ICs and different CPUs. Flipping the board over it looks like they just soldered the ROM chips to the appropriate pins beneath that slot and I really hope that is all they did (the quick and dirty way) on this Mac. Unfortunately I don't have my hands on a real cache module so I don't even know exactly what it looks like or how it might be wired.
And thanks all for the help and discussion.
