Monitor problem

[tombriz1]

I have a home built computer that I am trying to finish. The major problem I am having is with the monitor going to sleep as soon as you plug it into the video card. I have tried two cards, and the monitor goes to sleep as soon as they are plugged in to the cards.Computer specifics:
Motherboard: Biostar Tforce 570 SLI AM2 AMD Revision 5
1.Video cards:
MSI 6600GT Gameing
2.ATI Radeon 9250 128MB 64Bit DDR PCI
Computer Case is made by Frisby
Memory is 8 gig installed
2 hard drives, both are Western Digital 500Gig SATA
Power supply is 300 watts that came with the frisby case, but I have a 650 watt power supply on order that has six SATA connectors.
I am 67 years old, and have been building computers for personal use since the early 80's, but this has got me stumped. Maybe some of you youngsters can teach this old dog some new tricks. (grin)
Thanks,
Tom Brizendine
US Army Rangers (RET)

 

[Fiery_WA]

Im guessing you have turned the power settings to never?

 

[tombriz1]

I'd do that very thing if I could get the monitor to come on so I could see what I was doing. Got another new monitor I'll try with the computer.

 

[tombriz1]

OK, I hooked up the new monitor, and it said "NO INPUT SIGNAL", and went to sleep. That was using the video cards one after the other. Got a feeling it is with the power supply only having a four pin plug. New PSU will have an eight pin.