I have Phoenix BIOS and it displays the code 7F which says: Check POST error and display them and ask for user intervention. I have tried two monitors (both on DVI input) and two PCIe x16 slots on my motherboard. The video card is a 9800GT and before I switched cases (the same setup in a different case) it worked fine. The primary PCIe slot does not seem to work as the fan on the card doesn't work, I don't know if it ever worked, this isn't my PC and I'm not sure which slot it was in before. When I plug it into the other one, it does spin, but I still receive no output to the monitors. I can press the del key on my keyboard and the code displays 01, which is a reserved code? No description is given in the manual. Any help or suggestions would be greatly appreciated.
Edit* I don't think it's video card related as I put my Radeon 6850 in there and I still got the same code and problem. I have reset CMOS as well, to no avail.
Are you able to try the two video cards in another computer and do they work? What is the power supply that is in this computer? Can you also try the psu in another computer to make sure that it is working properly? If you have tried all these things and everything works in another computer then the logical conclusion is that the motherboard is no good or it has developed one or two bad slots. That is possible , I have had it happen to me.
I think it would be odd that it would develop two bad slots in a matter of hours. The computer was working perfectly fine hours before I switched cases. The 6950 works fine in my system. Always has. The power supply is 780 watts and I have not tried the 9600GT or the power supply in another system. It seems to be supplying power to everything as far as I can see. All 5 fans are spinning with their LEDs, the motherboard light is on, the case lights are on. I know that doesn't necessarily mean it's not bad or going bad, but I have a hard time believing that in a matter of hours it decided to crap out.