right turn on pc ok windows xp home loads then about 2 to 3 minutes later a siren sounding goes off from pc have just reinstalled windows xp home all went ok except for now there is an alarm going of comming from the pc
What mobo is it? The one I have (a Gigabyte model)has a windows program (EasyTune 4) that monitors all the fan speeds and temps of the CPU, system etc. It's an overclocking tune but I only use it to keep tabs on my system.
In this you can set the level at which an alarm should sound. EG System fan drops below 2000rpm or if CPU temp exceeds 60 degrees Celcius you can choose your setting.
Look in your BIOS to see if it has any alarm settings. These will be such things as CPU temp, CPU Fan speed may have simialr settings as mine does. it may be that one of these is set too low (possibly your CPU temp) and as the system warms it triggeres the alarm. It may be under Advanced BIOS Features, or you'll have to dig around in the menus.