This is a boutique built computer and am getting tired of waiting on tech support from the manufacturer, so I will throw up the question here.
First of all, specs:
Intel I7 3820
Gigabyte X79-UP4 Mobo
4gb x 4 Corsair Vengeance 1600 DDR3
Corsair TX750 PSU
WD 1TB HD
Windows 7 64Bit
Powercolor Radeon 7970
BIOS and all drivers are up to date.
When I got the computer it would only boot in safe mode when the monitor output was plugged into the DVI. If I tried to use the HDMI output, the computer would boot to the post screen then restart itself. After getting in through safemode, and updating all the drivers it would boot in normal mode, but I would get bad display artifacting.
Got an RMA on the video card and received an identical replacement.
With the new card the unit will power up the motherboard and all the cooling fans, but I have no display output or power to my usb mouse or keyboard. Removed and re seated the card several times, tripple checked that my PCI-E power cords were inserted fully into the video card, and tried both x16 PCI-E slots, with the same results.
I installed an older Nvidia GF 210 and everything works fine with that card in, although my gaming performance is understandably poor due to the outdated card.
Is the replacement card I received bad? Is it possible that the PSU is defective and not feeding the card proper voltage through the PCI-E power cords, but outputting proper power to the motherboard?
I'd say it is a psu issue, if even the usb is not powering up then the machine isnt really booting at all and hence no display. gf210 uses way less power than the 7970...
btw do you get any beeps during post? the case should have a small speaker connected to the mobo on the same header as the power switch and hdd light. no beeps means no post, one short beep for ok post and then there are several different kind of beeps for all the possible things that could fail the post process, including video card problems. (check the mobo manual for beep codes)
ok, no beeps means either there isn't a speaker or the pc isn't getting enough power on all the voltages it needs. 750w is plenty IF the psu is working like it should, it might be faulty.
If you feel confident poking around with the meter check all the other wires as well, 3.3V, 5V and 12V can be found on the sata power connector though the pins on the inside are rather tiny, might be easier to measure the voltages from the mobo main connector, you know where the wires go into the plug... Keep everything plugged in like they should, power up and measure.
Checked all my voltages, and everything seems ok. A nice even 12.0 volts on all my PCI-E cables all the grounds check good to. Everything on the 8 pin atx and the 24 pin ATX is what the mobo operator manual says they should be.
Talked with tech support and they are sending me a 3rd card to try...