My Computer Keeps on crashing. (need Expert help)?

[mmphd]

Once I was Extracting a VCD on my computer and that was the first time it happened. My Monitor's Light Went from Green to Orange(it turned off) , My computer lights (both red & Green) Went on continuously. The Power Button Didn't work and neither did the force restart button work. So I had to switch off my Power Supply.
As things went on, nothing happened for quite some time. But then it happened again. Then it started happening with less time between each crash.
Then It got to a point when it would crash when I entered Win xp.
I Installed a new windows, situtation was better but only after 2 days it starting agian.

Can any one help me on this issue?
Thank you

 

[Route44]

Do you have any Blue Screens when it crashes? If so, please attach your minidumps so that we can read them and possibly help you discover the culprit. How to find your Minidumps with ">" meaning "right click":

My Computer > C Drive > Windows Folder > Minidump Folder > Minidump files. It is these files that we need, not the folder. When you post back attach your minidumps to your post as you would a Word document to an email. If you have several first Zip them together and attach the Zip file to your post.

 

[mmphd]

No Blue Screens, I don't Get any indications whatsoever. All That Occurs is that the Monitor Turns off and both the Red and the Green Light Stay on Constantly. And my Computer Stops responding. When I am in that situation the only I can Turn of my Computer is but shutting the power supply.
Could It be Any thing to do with the Capacity of My Power Supply? ( It is 300w).

I am running XP Pro SP1 (At the Moment)
I have an AMD Sempron 2800+ (1.60 GHZ )
1024 PC3200 RAM
And a Winfast 760GXK8MC Motherboard.

If you need to know anything else just let me know.

Thank you For All the Help.

 

[Route44]

Yes, it can definitely be your power supply. In fact, as I read your first post I was suspicious that it was your power supply, but I wasn't sure thus my inquiry on Blue screens. What is the make of your power supply?

Have you done anything to this computer like upgrading parts or installing software recently?

 

[mmphd]

Yes, In February I changed My Motherboard and Processor From Intel To AMD & Winfast. And I Usually Didn't Connect My DVD-RW Drive. But I Have been Doing and that was the first time it happened.

If I need a new Power Supply Which Capacity Should I get?
But I would only get One if it is necessary and better for my system.

Thanks for all the help, It's appreciated