My computer is behaving in a most erratic manner in as much as it will not boot up from cold until I switch the power button off - leave it for a couple of minutes - then it will usually boot. It will sometimes boot normally, but more often it behaves as above. I am running Windows XP. Would very much appreciate any help. - thanks.
Yes it does make a difference to know that absolutely nothing appears on the screen.
It rules out a corruption of Windows, and implicates a range of hardware failings.
For instance the power supply unit may be failing. They don't often do so this way, they either go or won't go! This might be an exception! The motherboard which governs the switching of the PSU maybe going wrong, again usually it does of it doesn't
If there are no Beeps or strange sounds it s probably not the video card...... so
Try disconnecting the power to all data drives, include the floppy drives and any CD drives, pull the plug on your BB modem if you have one and then switch on.
You should see the various DOS screens and eventually (because you have disconnected the HD you will get a boot error and it will stop.
If you get this far you will have ruled out bith PSU, Mobo, and Video card, so try reconnecting the others one at a time.