New to this site, so I'm sorry if I violate etiquette. I have been having a truly frustrating problem with an older rig. I haven't even been able to get the thing started, so I don't have exact specs. I know however that it is a gateway dx4831. The problem originated with an aftermarket PSU that was installed with a new graphics card. It was a 500 watt Antec. I noticed one day that the fan was quite loud, and assuming that a loud fan was an ineffectual one, I decided to replace the PSU. After I replaced the PSU, which was identical to the old one, the PC lost all functionality. Upon booting, there was no hint of a display signal. The monitor I used is older, and it remains blue until input is detected. The computer will boot up, show signs of power (fans etc), but no display until it abruptly reboots after approximately 25 seconds. The motherboard is not equipped with any form of diagnostics(led's, speakers) to troubleshoot. I figured that maybe the PSU was defective, and I attempted to use a new one that a friend had ( Same wattage etc). The problem persisted. I removed every component and reseated it. Nothing. I stripped the computer down to bare bones (CPU, 1 stick of ram, etc etc) and still nothing. I tried clearing the CMOS(Though admittedly I may not have done it correctly) I will be the first to admit that i truly do not understand the forces that are at work here. If certain components are fried, I will honestly just buy a new computer, but I would like to fix it if possible. I was just curious what you guys thought it could be.