The led light are flashning but PC not booting or powering off need help on what to check .first thanks guys . All I can tell adout the specs are it has a M7VIG 400 mother board , KVR 333 mem / 256

Try pulling the power cord and then rebooting.
This will definitely shut it down.
When and if it reboots you may get a beep code.

Let us kow the results.
This will help us resolve your issue.

If you could also give us some system specs that would help also.

the led light are flashning but pc not booting or powering off need help on what to check .
That's not much info to go on. If my computer started doing this I'd first check the power connectors on the motherboard to ensure they're plugged in correctly.

Sounds to me like you have a faulty power supply or your motherboard burned out. However, it could also be something simple like a bad MBR. Like stated before, see if you can get a beep code. Good Luck!