Hello, I'm new to the community, but not new to the site. I have alot of troubleshooting experience but am working on a computer and am i guess stumped. It is a dell dimension 8400 that I replaced the Power supply (dead) still wouldnt post so I ordered up a new cpu thinking that would be the problem, still wouldnt post. Tested and seems it would be a dead motherboard so i ordered a new one, when I put the new mobo in everything seems to turn on and fans and hard drive seem to fire up but still no video. So I replaced it with what i thought was a known good video card and still no video out. And this is on the new mobo. I have taken out all the ram sticks and tested a single one in all the slots and it makes no differance. Even when I take them all out no beep so I'm not sure if I have the pcspeaker connected..I am getting a solid orange light on front, and no diagnostic lights on back. I'm not sure what else to try.... Any help would be appreciated?
This is pretty good: http://www.tomshardware.com/forum/261145-31-perform-steps-posting-post-boot-video-problems
Any dead card can cause this type of problem, even one that is ajar in the pci slot. Make sure you physically remove all the cards and the memory before you give up trying to get beep codes. The ref above has a good photo of the built in speaker pins on a MB and advice on how to get a MB speaker if you don't have one.
Any chance the new MB defaulted to integrated video and you don't have the header connected or the monitor plugged there?