Hello. This is my first post here and from what I have seen, this is the best site when in need of PC help. I have 2 PC's that are not working and I cant figure out why. The first one is a PC I have had for a while and upgraded multiple times. I had a case that was broken, so i moved everything out and installed it into a new case. The only thing I changed was I switched my 7900GT out with an 8800GTS. I also changed the Heat sink and fan from an AMD stock one to an aftermarket one. After connecting everything, checking it, I plugged the PSU in and tried to start the pc, but nothing happened. The green light on the motherboard is on and the Ethernet cable is flashing orange, but the HDD, fans, etc. are not responding. I tried using the switch from my old case and nothing worked. I put my old graphics card in and my old heat sink in and still nothing.......

The second PC, which is one I am building for my wife, will turn on just fine, however it sends no signal to the monitor. I tried using the VGA on the motherboard and using the 7900GT DVI. Neither produce an image on my monitor and I dont know what to do.

Thank you guys a lot....you are a huge help and I am sure your guidance will help me through my PC tough times.

Hi Welcome to PCHF-- thanks for the knd words-- hope we live up to expectations


On PC #1 the first thing to check is that the RAM is fully seated & examine all the connectors for bent pins/double check ALL conections

Second PC : did you try swapping the video cable for another one ?
Is that monitor new? or a spare you had lying around?
Reseat the video card?Check the settings in the BIOS regarding the video adapter? If it's default is to the onboard-- you would have to disable it in the BIOS before it would see the add-on card
Un / Re install the drivers ?

When I get home from work, I will most certainly check the Ram to ensure it is seated correctly. Would that cause the PC not to turn on at all? As for the second PC, I cant even get an opening screen on my monitor, so i cant check Bios. I tried using the on board video as well, and it didnt work. The graphics card was checked and is seated fine.....The monitor worked fine 2 hours prior and the cable is fine.