|Well, a 290x uses about 250 Watts (full stress), and an i5 4690k has a max TDP of 88 Watts. So, together, that's about 600 Watts. In total, you could be using anywhere from 750 to 850 (depending on Hard Drives, Motherboard, etc) - so yes, I believe a 1000 Watt PSU will suffice.|
Those are two R9 290 XFX, so I think two R9 290x's will work.
No, having one 2.0 PCIe and the other 3.0 won't really cause many issues, generally GPU's in crossfire will just run at the speed of the slowest card.
And this won't really limit you too much, most cards don't use hardly more bandwidth than a PCIe 2.0 x16.
This could potentially lead to Micro-Stuttering but the cause of this is really unknown.
I highly doubt that a closed loop water cooler could use 150 Watts of power, I think you'll be fine.
Yes, your components will be running considerably hotter, in my computer the GPU is usually around 55° C, whereas their temps were about 70° C.
In addition, their CPU was around 60° whereas mine are around 40°, though water cooling would certainly help this.
It's not specifically this case that causes higher temps, more so any mATX form factor case.
Yes, I would definitely suggest using an anti-static strap, though working on wood isn't nearly as bad as carpet.
Without a second computer you know works, it would be difficult to test any parts...you could hook up a the PSU to the motherboard and see if you get power to various fans etc. to make sure they work, then hook up CPU/RAM to see if you can get into BIOS...from there you should be able to see if it recognizes the Graphics Cards and HDDs.
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