hi, My pc has an intel p4 motherboard powered by 256mb ram,80gb hard disk..few days back, it was giving weird problems.whenever i switch on the comp,could hear the fan running ,the green nd red light used to blink. but while the comp is running, suddenly monitor goes off and even the keyboard does'nt respond. only the mouse is lit nd cpu's green light glows(can hear fan runnin)... after repeated trials, i was able to restart system properly...but nowadays, even repeated restarting does'nt help...only cpu is running and mouse glows..is it some problem wid ram? 'coz whenever i open 3 or more applications,there is more frequency of encountering the problem..please help

HI, welcome to PCHF.
We need more Data--
This could be:
Power supply
Motherboard
Video Card
Drivers

I suggest-- when you repost-- go into "My PCHF" under site navigation under "edit options" --scroll down the list.List all your hardware in the spaces ( include Brand names)-- at the top-- there is an option to "allow others to view my specs" click on yes. It saves a lot of time between posts if while you check something I can go look up your Motherboard manufacturer's site and read the manual.
You can also list your Operating System...all this is a great time-saver for us-- we can view everything quickly to refresh our memories... as we are all working multiple threads at once.This would be automatic from that point on-- so if you have another problem six months from now-- we can instantly know what you have.