intel celeron D356 512mb KEEPS CLOSING DOWN?

The monitor will always say 'no signal' until it gets one from the computer so it is possible it will always say this for a split second after youve switched on.
If its switched itself off ever since you bought it then its probably a hardware fault, take it back to the shop if its only 6 months old its still under warranty.
If its started doing it recently it maybe a software problem, try system restore back to before it started, or reinstall windows - should have restore disks with computer - NB. All your data will be lost.
www.diypcfix.co.uk

www.diypcfix.co.uk
August 2007

Intel make the chips not the computer so you don't have an Intel

If you are in the UK and it has done it since new take it back and get a refund.

t
August 2007