Hmm, trying to figure out why I'm getting memory errors in games on my FX5600 card which used to have a big Zalman cooler on it but I put a smaller regular cooler on it. It runs okay for a few minutes but when it warms up then reality in games starts falling apart with triangles heading off into infinity 🙁
MATS showed me that FBC is where the errors are so I've been trying to find out what Frame Buffer channel "C" data lines C12 and C15 look like on the card in the physical dimensions. There's no pinout of the FX5600 cards that I can find so I looked for schematics and found a few, including an MSI MS-8912 card which I've already got some good pictures of, so I can map out which chip is on which location of the card.
The result is pretty interesting, learned a lot about how BGA pinouts work with certain characters like "O" being excluded from the column naming letters. The BGA pins in the schematic are kind of upside down and only correct when looking at the card from the underside, so I used excel's transpose ability to flip it around so it's looking from the top instead:
The attachment fx5600-bga-pinout-diagram.png is no longer available
Looking at BGA stencils for the chip which is about all I can find of the layout, it certainly looks correct.
Since Frame Buffer channel C data lines C12 and C15 are both at the edge of the BGA, I bet that heatsink or an impact has broken their BGAs. The two pins I've got problems with go to the RAM chip in the top left on the front - hmm maybe it's the RAM chip, there was a bit of damage around that chip and I did have to resolder some capacitors, perhaps reflowing the RAM chip and verifying those capacitors will help more...