SAPPHIRE HD 2600 XT - PC WONT PowerOn When Plugged into ASUS M2N-E SLI

Hello,

I don't know exactly what is wrong with my Computer, it's a year old and was blue screening on occasion but would always restart and boot back up again. Recently i tried turning it on in the morning and it was not giving me any video on my monitor *No Signal* and it wasn't giving me the boot up beep messages. For awhile it was still powering the fans and making noise, but then it wont even do that anymore. If i have the graphics card plugged into either of my pci slots the power fan+cpu fan spin once then stop and it wont do that again unless i turn the PSU off and on again. When i have the graphics card uninstalled from the board the system boots up fine it sounds like, or atleast sounds and looks like it is. And it gives me 3 mboard beeps, (1 long 2 quick). I've tried alot of things, and with no on board graphics for my mobo and how it wont even get power anymore, i don't know what to do.
Also when it was still powering up, but not giving me any video signal the pc was running still i think. I have aol instant messanger set to autosign in and my friend said that i was online when i had my cpu powered up.

My pc details are as follows:
-X-Power 585 PSU
-ASUS M2N-E SLI NF500 SLI AM2
-Sapphire HD 2600 XT 512m GDDR3 PCI-E Dual DVI-I/TVO
-CPU AMD ATHLON 64 X2 5600 2.8g AM@ 2x1M R
-250 GB Western Digital 7k 16M SATA2 HDrive
-Sony MPF920 1.4mb FD
-ASUS 1814BLT DVDr/w burner w/ lightscribe
-Corsair XMS2 2GB: 2 x 1GB DDR2
-Windows Vista 64x Ultimate Edition

I really don't know what is wrong here and would really appreciate any help, the cpu was running fine for about a year before this (minus the occasional blue screens). Thanks in advance for any help
-Luke