I think it is good idea that you are going to get another graphic card and psu. Personally, I suspect the graphic card right at the begining, however, the crash dump never blamed directly to the card...
In the crash dump you just post, one with stop code 124, which is hardware related as I mentioned in earlier post, the other one is stop code 3B with exception code c000005 which can be related to memory.
Code:
BugCheck 124, {0, fffffa8006777028, be000000, 800400}
Probably caused by : hardware
Followup: MachineOwner
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BugCheck 3B, {c0000005, fffff96000182e19, fffff88003811eb0, 0}
Probably caused by : win32k.sys ( win32k!DCESpeedHitTest+55 )
Followup: MachineOwner
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