I couldnt find any abnormal temperature reading from the data you posted here or on speccy. All readings seem to be normal.
May be the GPU temperature changes due to the usage demand.
Can you check the CPU and GPU temperature by using realtemp from : http://www.techpowerup.com/realtemp/
speed fan from : http://www.almico.com/speedfan.php
and report back the temperature of GPU and each core of CPU.
Did you see the warning about ' abnormal power fan ' after the initial post?
I am still asking not to do any modifications, if you feel the popup issue is not completely resolved (which will be the case if you have used your own methods to fix the popups). But seek help from the malware removal section .
If you feel confident your pc is clean, please read the rest.
Is your sound / audio system working now? If not, try connecting the speakers to front panel speaker jack and check.
You may need to uninstall and reinstall the sound / audio chipset driver and check if no sound can be heared.
If your power supply is dying, the first symptom must be dead cooling fan of SMPS ie, to which the external power cord is connected.
And the power supply / SMPS will not notify it with a popup, just because it cant.
But if its your cpu or gpu cooling fans, then we may need to check the system. Thats why we need the readings.
Inorder to keep your system upto date, use secunia PSI from : http://secunia.com/vulnerability_scanning/personal/