Critical start-up problems.

I'm not sure if this is win-related but it probably is so that's why I post in the xp - forum

My computer/OS info:
win XP
Home edition
Version 2002
Service Pakc 2

intel
pentrium 4
cpu 1.5GHz, 512 mb ram

THE PROBLEM
For about one month, when i start the comp, the electricity goes on and the case fan goes on... but the computer doesn't start to access the harddrive and doesn't connect to the screen, at all..

So I turn the comp. off, and start it up like 30 seconds later and everything is fine

Last week it hasnt worked on the second attempts but on the third and fourth, so it's getting worse.

The one thing that I tried to do to fix the problem was to update the drivers for my geforce graphics card...but no difference.

Can someone please, give me some suggestions on what to do, or directions on what to look into?

 

Have you checked or ruled out the power supply? Can you try another one?

 

Thanks for the welcome.

I'm not as sure that it's hardware problem but I will look into your suggestions.

For two times at start-up it has stopped at the Verefying DMI Pool Data, point... so I'm worried that it has more to do with the OS or some software

 

Check your memory sticks . Sometimes when ram goes bad , it won't get to the boot up screen . Take out one first ---then try to restart. If it does nothing ---replace that one ---then remove the other one and try to restart again .