hi. i just build up a new pc with an old cpu motherboard memory bundle i bought from ebay.. after i put everything togther system powered on fine ,then i formatted the new sata hard drive and installed winxp sp2 everything looks ok.. after instalation pc reboted fine then i installed mother board driver and graphics card driver and restarted it loaded window fine. sound and graphics look looks working.. now i hooked up my old ide hard drive as a 2nd hard drive on ide channel .cause i wanted transfer lots stuff to the new sata drive. now after connecting the old hard drive i swtich on the pc but it made a continous bipping noise for 30 to 60sec than shut down automaticly.but this hard drive work fine with my old amd 2500+ system..tried again it will not boot up..then i remove the old hard drive and put everything back as it was at the new instalaltion but it will not boot up .it power on ok for about 30 sec or so then shut down on its own..one time it loaded window all the way into the desktop screen than it went off. the amount of time it stays on varies. couple of time i went in to the bios and checked the cpu temp it showed its running around 35c and the fan is on 2300rpm. i tried resetting the jummper ,swap the memory stick in diffrent slot (it has 2 512 ddr2 ram stick). ==one thing is that , the motherboard has a 24 pin atx power housing but i am using my old 500w 20 pin connector psu it goes in fine on the mother board but leave 4 pin empty.. could it be the psu doing all this cause it is 20 pin connector not 24 pin as the board.. but the pc booted fine at the 1st and 2nd time even i installed windows no problem... i am very confused.. plz help here is the spec (below ebay link for the bundle i bought) http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=6855025943&ssPageName=ADME:B:BCA:UK:31 cpu = P4 556 3.6 GHz cpu with VapoChill Micro High End Performance Cooler heat sink Motherboard = Foxconn 925A01-8EKRS2 memory = 1gb (2x 512mb) DDR2-SDRAM PC2-4300 (266 MHz) graphics card = e-geforce 6800 card hard drive = sata maxtor 250 gb 16mb cache sony dvd-rom psu = ebuyer value 500w 20 pin connector 3 years old . but working fine even now on my old machine wihich has 20 pin connector . any help will be much appreciated.. thnnks suhail

<<the motherboard has a 24 pin atx power housing but i am using my old 500w 20 pin connector psu it goes in fine on the mother board but leave 4 pin empty.. could it be the psu doing all this cause it is 20 pin connector not 24 pin as the board.. >> That seems a logical place to look for the problem, eh?

1st thanks for ur reply this motherboard does allow up to 2 ide hardware to connect it can be 2 dvd rom or 1 rom 1 hard drive ,i got this info from the previous user of the motherbord. but when i had problem after connecting the ide hard i took it off but still it won't stays on.but this time no beep just shut off after few sec. aanother things i found out that after it shutdown itself and i try to switch on it will power up but with in 10 sec it will shut down but if i leave it off for few min then switch on now it will stays on bit longer like 30 to 50 sec then goes off.. like this morning when i switched on it almost went to the desktop but sudenly it shut down.. but when i tried it gain in few min it did not go that far... someone else wa telling me this psu too weak to support a 775 Intel CPU.. what do u think ? i means its 500w pin conector aside. waht would be a good psu for this.. suhail

you can buy adaptors to convert 20 pin to 24pin plug. I reckon you need to sort that aspect of it.

And a bad 500w is worse than a good 350! What brand is it? It was not new, I surmise?