Video problems

I installed a new ASUS motherboard and a new power supply into my system. I updated the bios and all other drivers to support windows 7 64 bit Windows. I have installed all the latest drivers for every device. The system is stable as there is no crashing yet the system isn't smooth and the screen randomly goes black for a couple of seconds as if to go to sleep only I have the power set to never sleep. I don't get any error messages and this happens even though I'm in the middle of typing. I feel as though the problem is the integrated video but I haven't found a way to test it since I don't have a video card less than 10 years old to try. I don't even know if any of them work.
My HDDs test good, my 4g RAM test good (memtest86)


Here is my system info


Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Professional, Service Pack 1, 64 bit
Processor: AMD Phenom(tm) 9600 Quad-Core Processor, AMD64 Family 16 Model 2 Stepping 2
Processor Count: 4
RAM: 3839 Mb
Graphics Card: ATI Radeon HD 3200 Graphics, 256 Mb
Hard Drives: C: Total - 305242 MB, Free - 228875 MB; F: Total - 152623 MB, Free - 54011 MB;
Motherboard: ASUSTeK Computer INC., M4A78-EM
Antivirus: Microsoft Security Essentials, Updated and Enabled


Do you know of a way I can test the integrated video?


Thanks
Jeanette