Unable to boot - Please help!

[affy]

Hi,

I have a problem booting my pc.
It has been workign fine an I turned it off one night and now it won't boot, it won't even get power.

I have a Jetway V2DP motherboard with an AMD Athlon XP 2.0ghz cpu.
my RAM is 1GB (2x512MB) PC2100 266MHZ DDR CL2.5v ECC alongside a GForce FX 5500 graphics card.
sound card is onborad and mouse is USB. Keyboard is still PS2, and internet is connected through a home networking LAN which is connected via a BT Voyager 205 ADSL router.

I don't know what version of BIOS it is runnning and now have no way of finding out as the system won't even start.
I have a 400w ATX Mercury power supply with a "power" switch on the back.
When i turn the PC off, I always switch this off as it sounds like a TV onstandby otherwise.

When I came to turn this on again, I heard a 2 tone siren (like a police siren).
The PC does nothng else, just plays this siren.
When I turn the ATX "power" switch off, it stops (I'm assuming that it cuts the power.)

In summary, it seems to me that if there is power, then the siren sounds, and I can only stop it by turning the power off!
It won't even let me turn the PC on to try and boot.

Please help as it was working fine beforehand and I'm banging my head harder each day.

thanks in advance,

Af

 

[iss]

try another power supply, it sounds like the one you have is bad. PSU's should not be making noises when the computer is off.

 

[affy]

Hi,

Thanks for getting back to me so quickly.
I have tried a 250w unit with the same result.. do I need to try and get a 400w one or shoudl that do it?
i've tried unplugging everything too... HDdisks, DVD and Cd roms, graphics card memory etc.. still the same!

Af

 

[iss]

the 250Watt unit may not be delivering enough amps. But that is not a real high powered unit so it is hard to tell. if theother PSU was bad it could have damaged the mobo.