PC Specs
OS Name - Microsoft Windows 7 Ultimate
Processor - Intel(R) Celeron(R) CPU E3400 @ 2.60GHz, 2611 Mhz, 2 Core(s), 2 Logical Processor(s)
Installed Physical Memory (RAM) 4,00 GB DDR3
ATI Radeon HD 5600 Series
Disk drives - WDC800JD-60LUA0
Hello!
I'm facing a weird problem on my PC, it started yesterday, I was playing a game and out of nowhere my computer just started to randomly flicker black screen. Something like this has never happened before, I've tried a lot of different things to fix this. My GPU, CPU temperatures and usage are at normal levels. I downloaded 'PerformanceTest Benchmark Software'. With this program I did some 3D graphics tests, what's weird is DirectX 11 test was done flawlessly no flickering, not minding the low fps (~16fps), DirectX 10 was just low fps(only ~3-5fps) and again no flickering, but DirectX 9(simple,complex) tests went terrible I was only able to see about 2 out of 15 seconds of the test, the rest was just black screen. Now whenever I go into a game it's impossible for me to play it because of the flickering. For example on youtube I sometimes am able to watch 360p videos with no problems, but when I put it on 720p it starts to flicker. It even flickers as I am writing this right now.

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