Random PC freezes

I removed all the external things from my pc(external hard drive, camera, scanner and sound speakers) except from the router and tested my pc with 1 ram at a time. I had a black screen in every try. So it shouldn't be a ram problem.

I downloaded Unigine, Tropics and Sanctuary and run the benchmark mode in all of them twice. Here are the results:

In Unigine it passed all the stages both times. The results are: FPS 24.4/24.4 , Score 614/615 , Min FPS 8.6/12.1 and Max FPS 56.2/58.

In Sanctuary the first time i had a black screen in stage 5 and in the second run it passed all the stages with FPS 48.2, score 2043, min fps 28.4, max fps 62.8.

In Tropics in the first run it passed all the stages with FPS 36.8, Score 928, min FPS 23.5 and max FPS 72.6. The second time i runned the Tropics i got a black screen.

All these tests were made in DX11.

The scores are very good. The black screen issue is most likely due to either the PSU, GPU, or motherboard. The only way to find out which for sure is to start swapping components. Do you have any friends, coworkers, classmates, etc. that you could borrow a PSU and/or GPU from? Try to get a PSU with the same or close to the same wattage (a little higher would be preferable if it is not the same). Also, try to get a GPU with around the same specs.

If your GPU is under warranty, you could also contact the manufacturer and see if you can get an RMA.

Also, on the outside chance this is software/Windows related: Clean Reinstall - Factory OEM Windows 7 and try not to install any software but the Unigine software to test the graphics.

Hey there. I can get from some friends of mine a geforce 9500 GT GPU and a 430watt PSU. Should i test any of them? My PSU is 500w and my graphics card is nvidia gts 250.

Try the graphics card first. If that checks out, try your card again and see if you still have problems. If your friend's card causes the same problems, try the PSU with your friend's card still installed.

Make sure to uninstall your nVidia drivers prior to removing your card and replacing it with your friend's card. One of my previous posts gives steps for uninstalling the drivers.

Hey there again. So i tested my pc with my friends graphics card and no black screen occured. I also checked my GPU and it had a lot of dust(i forgot to clean it last time), so after i cleaned it i put my GPU back and everything was working fine. I runed all the programms that always caused a black screen and it seemed the problem was fixed. But after some hours i came back home and i got a black screen again..

I can't test my pc with my friends PSU. Can i check anything else?

I would recommend cleaning the contacts and making sure all dust is out of the motherboard slot.

"Use an ink eraser or an electrical contact treatment, available at electronics supply stores, to ensure adapter card contacts are clean" (Bug Check 0x7A: KERNEL_DATA_INPAGE_ERROR).

As you add and remove hardware, follow these steps for ESD safety:

1. Shut down and turn off your computer.
2. Unplug all power supplies to the computer (AC Power then battery for laptops, AC power for desktops)
3. Hold down the power button for 30 seconds to close the circuit and ensure all power drains from components.
4. Make sure you are grounded by using proper grounding techniques, i.e. work on an anti-static workbench, anti-static desk, or an anti-static pad. Hold something metallic while touching it to the anti-static surface, or use an anti-static wristband to attach to the anti-static material while working. If you do not have an anti-static workbench, desk, or pad, you can use your computer tower/case by finding a metal hold in it, such as a drive bay.

Once these steps have been followed, it is safe to remove and replace components within your computer.

I cleaned all the contancts and the dust from all the fans and i also used this Google.

The first time i booted my pc after i cleaned it, i runned the programms that always caused a black screen but they were running fine. After some hours that i used my pc again i got a black screen.

Time to start thinking about replacing parts. Try to buy parts from a store that will allow you to return them if they do not solve the problem. The PSU is usually the easiest to buy and return.

Hey there. I have decided to send my pc back to the store where i bought it, so the technicians can test it, find the part that causes the black screens and replace it. Thanks a lot for the help so far. I will inform you of what caused the problems when i get my pc back in about a month.

By the way can you give some more information about the freezes i used to have and were fixed when i changed my northbridge voltage to 1.55 V and my first four RAM timings in the BIOS to 5-5-5-16 instead of 5-5-5-18? What are these changes and what did they affect? Why the default settings caused freezes after 3 years after i bought the pc? Also should i set these settings to default before i hand my pc over to the technician?