I recently bought a damaged 290. The smd cap shown was smashed. I don't have the specs or the means to measure the capacitance of one of the good caps. Instead, I just swapped in a same-sized cap from a donor 8800gt.
The card works now and is completely stable with the stock bios, as well as with much more aggressive memory timings. However, I'm simply unable to go beyond ~1325mem stably. Stock rom, the hynix mod rom, manually applying the 390 mc timings, or any other testing have all proven fruitless.
Stock bios has mem at 1300, and it seems that with 390 mc timings, it should be able to hit 1500.
Further, it seems when exceeding ~2gb of memory usage (e.g. when mining at higher intensities), errors are produced (hwinfo shows no memory errors as long as I stay within 1325mhz).
So I'm wondering if this capacitor is related to the memory / memory controller. Or better yet, if anyone is able to determine the actual specs so I can replace it with a proper one.
edit: it's a reference 290 (sapphire tri-x)Edited by ziddey - 4/13/17 at 3:04pm