My computer freezes for no reason

[Kiran25]

I don't know the exact reason why my computer is freezing. Here is some detailed information on what happened. I was having certain issue with the system. It was freezing before also, but I removed some programs from control panel > add remove program. Things went back to normal. I am using an usb modem in my system. The system takes a long time whenever I start the screen and the dialer is launched at the startup. I tried installing and uninstalling many times but nothing worked out. I think the dialer is simply not compatible with my operating system. Then I run some updates of Windows. It worked nicely. The system was almost turned on for more than 2 hours after
shutdown with an message saying that - do not turn off the system, installing updates. I even went to that process and completed properly.

But suddenly after some time the system responded slowy. When I press Windows Key + E to run My Computer the entire screen freezes and only white background is displayed. After some long time the screen shows up. I added a new ram and can that be a cause. It was fixed by an friend and he did all things well.

[Enriquee]

You might need to re-install your operating system. Do this run Task Manager. In that go in Performance tab and then click on Resource Monitor. See that which service is eating you entire processor. The system freezes mostly when the cpu is fully utilized and that is caused by a virus which tries to create a connection with distant server. If this is an issue then format the system at once. Second you can also verify your hard drive for slow performance. A poor rpm performance can cause slow response and freezing of your system.

[DanielV]

There is an tool called Memtest. This tool scans your system on boot for testing your memory chips. You can load this on a disc and boot your system with it. Load the software on your disc and boot your system. Perform the diagnostic and check back.

[Aleksandra]

When using a PC, you may experience instability and functional abnormalities you must run diagnostic utility. Memtest is one of it. The reason behind those abnormalities can be due to malfunctioned RAM or due to a failure or an incompatibility between ram sticks. Memtest will help you to find information your RAM errors. Better do that and then see. Remove the ram and test your machine with your old hardware.