AMD 5200+ overheating problem

[Azure101]

Hi there everyone,

I've had my PC for around a year and a half now...

Here's my Spec:

Asus M2N-E SLI motherboard
4870 1gb
750W PSU
4GB Corsair ddr2 800MHz ram
250GB HDD
AMD 5200+ (2.7 Ghz)

And i have recently purchased the coolermaster 335 case and reapplied the thermal paste to the CPU.

Ever since i've had the pc i've had serious CPU overheating problems, however what is very strange is that it can overheat when running programs like Firefox and literally the second i close firefox or any game i'm playing the CPU temperature can go from 80C+ back down to 20 degrees... I can't successfully get through 3dmark06 because during the CPU test my pc just shuts down... I don't know whether the sensors on the motherboard are faulty but surely it cant be a cooling issue if the temperatures drop THAT quickly?

EDIT: I have ordered a new heatsink but i'm not even sure that's going to have any effect, the one i have ordered is:

http://www.overclockers.co.uk/showproduct.php?prodid=FG-000-AR&groupid=701&catid=57&subcat= due to it receiving very good reviews

 

[Azure101]

Thanks for the reply Plec!

I'm currently using Coretemp and speed fan to mointor my temps...

I've checked the temperatures in the bios after it has shut down due to overheating and yeah they read very similar to what coretemp says.
I want to try updating my bios but i'm scared

 

[Azure101]

http://static.tigerdirect.com/pdf/Asus_M2N-E_SLI_Manual.pdf

There's the manual, I'll take a look... If i can't find out how i'll report back

EDIT: Just taken a look.... says i need a floppy disk.. As you mentioned earlier would a USB drive be ok?

 

[Azure101]

Thanks Amonlym, Plec i took your advice and flashed the bios... it was actually very easy now the temps are much more stable... no more dropping 50 degrees in like 1 second! I am however still overheating but i feel the readings are much more reliable and i will see how the new heatsink fares.

Thanks everyone! I'll let you know how the new heatsink affects the temps

 

[Azure101]

Well fitted the new heatsink temps haven't gone over 40 yet even when running 3dmark06! :O

Thanks a lot Plec!