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I have another 2915 that gives 3 short beeps continuously when its powered on. This happens with any RAM in any slot. 1 stick or both. When I remove the RAM and power it up it gives normal "No RAM installed" beep. Thanks, have a good day.
CPU, RAM slots, traces, all not fixable really. You could check the slots with a RAM slot tester card. I don't bother with the 3 beep boards, even if you fix it it will be back next month claiming warranty on a dead GPU, avoid.