I put this build together on Wednesday, and have run into a problem: my video card doesn't always work. Apologies for the wall of text, but I wanted to describe the problem and symptoms in detail because its just so weird.
When I bread-boarded the system before putting it in the case, the video card worked fine. It also worked fine the first night I used the computer. When I powered up the next day, the system turned on, but showed simply a black screen. With speakers plugged in, I could even hear Windows load.
So Thursday night, I opened the case back up, double checked all my connections, and re-seated the video card. That didn't work, so I changed the display to use the on-board graphics, which were working fine. In the BIOS, it showed that the card wasn't even recognized as being in the PCI slot. I tried re-seating multiple times (5 or 6 times, probably) until the card started working again.
Friday night, I come home, power up, and see a black screen again, with the Windows start-up sound playing in the background. I try powering down and back up again multiple times. Switching to on-board video works fine. I check the BIOS, and we're back to no card in the PCI slot. So I leave the display hooked up to the onboard graphics and use the computer for 10–15 minutes. Then I shut down, switch over to the graphics card, and everything works like it should. I think it's probably important to note that I never took the case off/unplugged/re-seated anything. Same deal Saturday and Sunday.
Once the system successfully boots with the graphics card, it doesn't seem to stop working, until I try to use it the next day. I've been able to use it for hours at a time without problem, once it successfully boots.
So... who's got ideas as to what's wrong? My current theory is that there's a bad connection/solder point that doesn't like the cold. (It gets down to ~20-30 Fahrenheit during the day in the house.) Thanks for any help you've got!
Here's the build:
CPU: Intel Core i5-3470 3.2GHz Quad-Core Processor
Motherboard: ASRock H77M Micro ATX LGA1155 Motherboard
Memory: Crucial 8GB (2 x 4GB) DDR3-1333 Memory
Storage: Seagate Barracuda 2TB 3.5" 7200RPM Internal Hard Drive
Video Card: HIS Radeon HD 7850 2GB Video Card
Case: Antec Three Hundred Illusion ATX Mid Tower Case
Power Supply: Corsair Builder 500W 80 PLUS Bronze Certified ATX12V
Agree with goldsauce. The real telling part is that the BIOS does not recognize the card. Either it is underpowered which is extremely unlikely with your power supply, the pci slot on the mb is bad which is not the case since you can get the card to load later, or the card is bad.