My build stops sending signals to the monitor after some time

[ellohel]

I just finished building my computer and when I was going to install Windows 7 on it, I encountered a problem. After a couple minutes of me leaving it alone, my computer stops sending signals to my monitor. The fans are still spinning, the lights are on, but the monitor is pitch black.

Now I could dismiss this as the how the computer sometimes acts during installation of the OS, but this also happens when I leave the machine alone for a few minutes in the language selection section. I doubt that's supposed to happen.
Please help, thank you very much. Below is the build that I have, plus an optical drive I can't find, and a GPU from my old computer (Sapphire's Radeon HD 5770), also that I can't find in pcpartpicker.

Again, thank you.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-3570 3.4GHz Quad-Core Processor ($214.98 @ NCIX US)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler ($27.98 @ NCIX US)
Motherboard: ASRock Z77 Extreme4 ATX LGA1155 Motherboard ($129.99 @ Amazon)
Memory: G.Skill Ares Series 8GB (2 x 4GB) DDR3-1600 Memory ($39.99 @ Newegg)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($77.99 @ NCIX US)
Case: Antec Three Hundred ATX Mid Tower Case ($39.98 @ NCIX US)
Power Supply: Rosewill Hive 550W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply ($66.27 @ Amazon)
Total: $597.18
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2012-09-22 20:40 EDT-0400)

 

[velosteraptor]

Does the monitor work on another computer?

 

[AntiZig]

you got 3570, non-k version? spending so much money on good board and HS only not to overclock? =/

What cable are you using to hook up to your monitor? dvi/hdmi or vga? try swapping if possible

if you move the mouse after the monitor goes blank does it come back up? if yes, then it just goes to power save mode