After much research and trial and error, i believe i have narrowed the issues i've been having with my computer over the past month down to GPU related. I have a custom built rig with the following specs: RAIDMAX SMILODON ATX case GIGABYTE GA-870A-UD3 AM3 AMD motherboard XFX HD-567X-ZNF3 Radeon HD 5670 GPU Antec EarthWatts EA650 650W PSU AMD Phenom II X4 925 Deneb 2.8GHz CPU G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 Western Digital 1tb HDD Windows 7 64 bit Professional Computer was built back in July and had been working wonderfully until maybe a month ago. it would randomly reboot, and give me BSODs. Since then i have run multiple tests on my RAM, hoping it was that. I have also reinstalled windows a few times. the HDD has been checked and is fine. I do believe the PSU is fine as well. What leads me to believe that graphics card is the culprit is that recently my computer screen has locked up and displayed colorful pixel bars going horizontally across the screen. I had never seen something like that before. I had downloaded a 3D benchmark program and in the middle of the stress test with the latest driver installed, my computer rebooted. I've also walked away from it only to come back and find the monitor to be blank (black), with it telling me no VGA signal or input. Just today, the screen locked up on me again while only opening IE (i usually use chrome but havent downloaded it since my recent format), showing vertical lines on a white background. Is there anything more i can do to determine whether or not it is for certain my graphics card? I'm just looking for any advice/opinions. thanks in advance.