Why does my screen flicker and my laptop crash?

I have a Dell laptop with Windows 7 on it. Every so often the screen goes exactly like the one in this picture (Why does my screen flicker only in Windows 7?) and freezes. Nothing works and I need to switch off the laptop manually. I've run all sorts of hardware tests with help from the Dell hardware support team. They found nothing and say it's a software problem.

This usually happens once a week but on a very hot day recently it happened five times within 8 hours. So I'm wondering if it could be overheating. The Windows refresh rate is set to 60 and the screen resolution is set to 1366x768. If it is overheating, what can I do to solve the problem?

And what kind of software problem could it be? And how to fix it?

Solution 1:

Based on the fact that you say its worse on hotter days, my guess is that either your specific unit is faultly, or their is a fault in product design.

Neither is out of the question, I had a Dell laptop that had similar video problems. This isn't the first time Dell has had this problem:

You have the option of updating your BIOS, which will likely turn up your fan speed and potentially make your notebook slightly louder, in hopes that you don't have issues down the road

Solution 2:

That does not look like a software problem at all, but more like you mentioned yourself, a overheating problem.
Either your graphics card, RAM and/or your CPU could be overheating. I would put my money on your graphics card and you could put it all to a test.

CPU and RAM test

Download HWMonitor and Prime95 (x64) / Prime95 (x32) and install them both.
Start up HWMonitor and check the temperatures under your the name of your motherboard and graphics card. It looks something like this:

NOTE
Not all graphics cards support this, so you might not be able to see the temperature.

While having CPUID open, fire up Prime95.
Make sure that Blend is marked and click OK to start testing. This will torture your CPU and RAM, so go back to HWMonitor and monitor the CPU temperatures, if it's getting really high (70+) then you should be worried.

GPU test

Start by downloaded Furmark and install it and fire it up.

The program should identify your graphics card and you should have to "burn-in" buttons, click the one labelled 15 min (You should not run it longer than this). This test really gets your GPU high temperature, so be sure keep an eye on HWMonitor and you could get the same flickering as on your image.