PC warning light and sound

[efiste2]

Last night my trusty Sony Vaio desktop started beeping and flashing the blue power light to orange and then back to blue. This happened every5 minutes or so. I think it could be a tempreture alarm, but im not sure, so does anyone know what it is, and also does anyone know of a good PC speed checker to see if the PC is upto its normal speed. and not getting overheated. I have check inside and de-dusted it, and the heat-sinks are all attached and fans working. Any advice would be most appreciated

 

[Mhz]

Is it still blinking and flashing after cleaning the crud out? If so it's probably not overheating unless you keep it in the oven.

Try CPUID CPU-Z and HWMonitor for system speed and temps etc.
http://www.cpuid.com/

 

[opps]

have you tried to remove the ram and put one stick back at a time.

cpu over heat normally justs stops the pc dead in it's tracks.