Hi,Are you able to try a different GPU? or perhaps your mobo has onboard video? this would be helpful to rule out GPU issues.It would be wise to test your power supply as well, it is possible for these to cause louder fans when they are struggling. Is there another monitor you could try?There are so many possibilities.But, the easiest cheapest thing (and a common fix) to try is re-seating you processor. To do this you will need to re-apply your thermal paste(recommend using a . In my opinion anytime you remove your heat sink you should use fresh paste. Be sure to familiarize yourself with the locking mechanism for your CPU, do not force anything. Be very careful not to bend any pins on you CPU. Clean off all the old paste and re-apply (http://www.maximumpc.com/article/howtos/howto_install_cpu_and_apply_thermal_paste). Firmly seat the cpu and lock it into place. If your machine is old or heavily used your paste can dry out (or sometimes even burn when overclocking) and no longer transfer heat properly.Also, I keep a few extra parts laying around to make testing easier, ask around, you may have a friend with what you need to narrow down your issue.