XPS 210 Bootup Erratic, Help

My XPS 210 has a new motherboard and a Westen Digital refurbished disk, it has started a new trick. If I shut down and boot up in a short period of time, 10-20 min everything works ok,

If I boot a few hours after turnoff it will startup for 10 sec, then off for 10 sec. on for 10 sec, then off for 10 sec. on for 10 sec. then beeps, off, then on with message "windows Error Recovery" with a select "start normally choice. I select this and it boots ok.

This is very frustrating, I assume it is a sign of a furure failure.  Help please,

Thanks for any help you can give me.