Dell Optiplex 755 DT Fans

[kman1960]

Hi all just got done with the upgrade new PSU,CPU, EVGA 640 and 8GB mem,SIIG Sound card 5.1, running Win 7 HP.The power supply is a ATX 350W. When I turn on the computer all fans start
is the DT supposed to work this way and it is loud. The Company where I bout the PSU no longer makes this model F5114 spoke to him 2 days ago he told me to replace the PSU fan. I know this wont stop the fans running all the time. So what do I try to stop this.

 

[Kisianik]

Which fans are loud, CPU or PSU? If not sure, open the case and listen, or better touch each one for vibrations.

 

[kman1960]

It would be the CPU Fan that is the loudest but the PSU runs all the time

 

[Kisianik]

Is your PSU looks new or used, could be just dirty inside. Since it is proprietary form factor, you don't have much choice. So, if it would be me, I would open PSU box without pulling any cables, just a cover, if possible and look at fan, it could be defective - something bent or touching, not sure. If you get to the point changing PSU fan, you would not stop it from working all the time, but you might be able to eliminate the excessive noise.

For CPU. Do you have any monitoring software to see your fan speeds and temperatures?
May be you did not applied thermal paste well, or used low grade thermal paste and your CPU just runs hot?
What was your CPU upgrade, original one and final one?
Have you changed heatsink to copper (or do you have copper)?

Please answer those questions, all of them.