Russel sent me an After Burner motherboard which was showing a bad RAM chip in the test menu, and he also shipped me an SSR board which had a broken solid-state relay, and which had some delamination of the copper traces due to someone having pushed down hard on the relay, ripping the copper traces off the board.
The original SRAM chips on these boards seem to be NEC 4364CX-12L chips, 8Kx8 SRAM in a 28-pin 300-mil package.
I haven't found a cheap source for these parts.
600-mil SRAMS with the same pinout are widely available, though, so I picked up some replacements (6264's) from http://www.bgmicro.com/ for about $1.20 each.
The original parts were spec'ed at 120ns, and the schematics for the motherboard show this also. The replacement parts I used were actually rated at 150ns (because that was all I could find on short notice) and they seem to have held out OK.
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| Here's the old and new SRAM chips, side-by-side, old one on the left, new one on the right. |
| I installed a socket in location 31 after removing the old (bad) SRAM chip. This chip was the one showing up bad in the test menu. |
| I needed a 600-mil to 300-mil adapter. These can be bought from various places, but I was in a hurry, so I made one myself. |
| Here's the bottom side of the Adapter. Nothing exotic. |
| Here's the Adapter with the new chip installed. |
| Here's the adapter with the new SRAM chip installed on the motherboard. |
| Here's the bottom of the repaired SSR board. To repair the missing copper traces, I just took some 12 guage copper wire, flattened it a bit with some needle-nose pliers, soldered it to what was left of the traces and component leads. This worked pretty well. |