Today I put my pm Systems computer into the case holding all the systems, and tidied all the cables with velcro straps. But after this it refused to startup and after the initial power on beep, it gave 8 beeps in rapid succession. Clueless I was
So I went downstairs to check the manual which did not help, no troubleshooting paragraph. Ok, lets try the internet...
http://www.bioscentral.com/ Yeah! 8 beeps on my system told me the video card was the bad boy.
Most probably the card had come a bit loose or something else happened. I don't know.

Any way, this is just to provide you with the link to boiscentral which was where I found help.