ABIT ST6 w/RAID, continuous 2-beep/2-tone "siren" sounding beep. Tried: changing memory, flashing bios(award), resetting cpu parameters, loading default bios values/read various FAQ's. Windows will load and beeping stops until I execute a program/feature or simply navigate in OS.(this sounds like memory?) Device Mgr. shows ! at PCI Multimedia audio device, however, drivers are installed. CPU: Celeron 1.0ghz. All was working just fine until I changed "yes" to "no" in bios for the pnp OS installed setting! Then unit would not reboot and I jumper discharged the bios and removed the battery (prior to flashing the bios) to get unit to reboot.
Any help/advice will be appreciated.
Thanks

Hello Ted

I'm rather astonished that you would disable the "Plug-n-Play" operating system support and expect your PC to work!
Yours is an up-to-date PC and probably ALL your hardware items are "Plug-n-Play" and do not have manual settings available?

Surely that means none of your hardware can be allocated resources!

It may be that the default values to which you reverted are not precisely the correct ones for the hardware you now have. [Has your hardware been altered since the machine was first assembled?]
Did you make a note of your BIOS settings when the PC worked ok?
If you didn't your going to have some task ahead.
You'll need to get to know your BIOS and what all the settings mean and try and tweak them until they're right.

A continuous two-tone beep in most modern boards indicates a CPU fan or heat problem.

If your BIOS has temperature monitoring get the temps and shut down the machine. (Post the temps here, from a known good machine, don't use this one) Then check to make sure the fan/heatsink are properly set up.

# A two-tone siren, generally caused by overheating or out of specification voltages

So also check your power supply....what do you have?

PnP OS shouldn't matter in this case, a PnP BIOs will take care of the cards that have no manual settings, The PnP OS setting informs the BIOS that the OS is capable of mucking about with the resource assignments (IRQs and addresses) and to to let it do that.....

Hello mjc

Here's a chance for me to learn.

Would I be right in taking from what you say;
that a plug-and-play BIOS will detect the recource assignments required by plug-and-play hardware and allocate resources to them.
That if the plug-and-play operating system support is then disabled any attempt by the O/S to change those assignments will be ignored.

The question then arises:
What if the O/S has a good "reason" for attempting to alter the assignments given by the BIOS.

I'm interested in this because I have an NIC card which get's disabled every second time I hot boot but is never disabled if I cold boot.

If this is off-topic I apologise but this is too good a chance to miss.

Thanks to all who responded to my perplexed query. I have no problem letting the BIOS select where and what it wants to allocate...my reason for changing the OS setting to no.
As it turned out, the problem was a low temperature setting in the BIOS. The beeps were a cpu heat issue. Temp setting was made, unit is back in service.
Thanks again,
Ted