Dos boot up screen keeps restarting?

[Andyk-9]

Hello everyone

I have a few old bits laying around and a family member wanted a computer just for emails, online shopping and facebook so i said i have a few bits hanging around just need a motherboard. So i got a cheap MB from ebay tested and working from a small company..

Now dont laugh when i tell the specs lol..

NEC 945G-M4
Intel Pentium 4 650 sl7z7 3.4ghz
3 x 1GB DDR2 800
bfg nvidia geforce 8800 gts oc2 512mb

1 X Sata 500gb Hard drive
1 x Sata DVD Reader

550wat OCZ PSU

Now after contecting everything, i swithed everything on and the dos boot up screen shown everything i had connected, then it restarted and in a cycle. I can get into the Bios and its fine, i then tried booting from the DVD rom so i can install windows but as soon i press a key to boot from rom drive it just restarts.. If i was to leave it, it will do the same.. Does anyone know what could be causing this?

What i have tried.

Another CPU
Tried using just 1 ram at a time
Took out the GFX card
Tried an IDE Rom and IDE Hard drive

I have never come across this before and its baffeling me..

Has anyone come across this?

Kind Regards

Andy

 

[HangTime]

This is going to sound a bit stupid, but are you sure you are pressing the key fast enough? I had an issue back in the day whereby there was a monitor delay between the post screen and the message saying "press a key to boot from cd" meaning if I waited until I had read it, it would likely be too late and it would try to book from another device.

Solution was to just sit there hammering spacebar during boot up to make sure I didn't miss the window of opportunity.

 

[Andyk-9]

Sorry for a very late reply. It turned out the MB was a fault..