No mouse or keyboard lights, computer wont bo

Hello,







1
A455-2866
Asus M3N78 PRO Motherboard - Socket AM2+, Geforce 8300, ATX, HDMI, SATA, Gbit LAN, Hybrid SLI

MPN: M3N78 PRO

1
C13-6082
Corsair Dual Channel TWINX 4096MB PC6400 DDR2 800MHz Memory (2 x 2048MB)

1
C13-6082
Corsair Dual Channel TWINX 4096MB PC6400 DDR2 800MHz Memory (2 x 2048MB)

1
CP1-AM2-9500
AMD Phenom 9500 Processor HD9500WCGDBOX - 2.20GHz, 4 x 512KB Cache, 1800MHz (3600 MT/s) FSB, Agena, Quad-Core, Retail, Socket AM2+, Processor with Fan

1
L12-1051
Lite-On PLDS DVD-ROM/CD-RW Retail Combo Drive - 52x32x CD-R/RW, 16x DVD-ROM, Black

1
TSD-500AS6 BM
Seagate 500GB Serial ATA HD 7200/16MB/SATA-3G

1
ULT-LSP750
Ultra LSP750 750-Watt Power Supply - ATX, SATA-Ready, SLI-Ready, 135mm Fan

Windows Vista Home Basic 64 Bit edition
So,

The build went fine and the computer was up and running. But when she went to use it one day, the monitor was saying that there was no signal from the computer. I am using the onboard video, so I know if cant be a vid card issue. I have all the motherboard drivers updated. When I restart the computer, I don't get any beeps, and her mouse (laser mouse) and keyboard dont light up. There is hard drive activity, and the power light is lit. I tried taking the memory out and starting the computer, and got a series of beeps, so Im pretty sure the motherboard isn'T the problem. I reseated the memory, and the computer booted up to windows and worked fine for about an hour, then when I came into the room, there were multicolored lines going through the top of the screen, and I was getting no response from the keyboard or the mouse to restart it. So, I restarted it manually and it would boot into windows, and then the same thing would happen with the multi colored lines. Sometimes, the same problem happens where the computer wont beep or bootup, and the monitor says"No Signal". It isn't the monitor, because I just purchased a new flatscreen too. I was using an old CRT before the flatscreen, and getting the same errors, and the same multi-colored lines. Do you have an opinion on what the problem might be? This really has me stumped. Lemmie know if you can help or if you need more information. Thanks !



Jon