Basically, my case (Silverstone PS07) has two 120mm intake fans at the front, and another 120mm exhaust fan at the back which I installed. The bottom one of the two intake fans works fine, but the top one has various problems. Sometimes I'll have to turn my PC on and off several times before it will start spinning, but even when it does start it's at a much lower speed than the fan below it. When I built the system a few weeks ago, the problem was present right from the beginning, and giving the fan a small nudge would help it start spinning, albeit still at the reduced RPM.
Using SpeedFan, I can see that the working fan is spinning at 1400 RPM when the system's idle, and goes up to around the 2000 mark when I'm playing a game. However, the faulty fan spins at around 450 RPM, and only spins at a maximum of 650 during gameplay. Obviously this means it is not functioning properly. Going into my mobo's BIOS or SpeedFan's settings to try and change the speed of the faulty fan achieves nothing, making no difference whatsoever.
A final point of note is that I recently opened up my case and tried swapping round the front two fans connections on my motherboard, to see what happened. This resulted in the faulty one working straight away, but still at the slower speed, whilst the working one now required a nudge to get it to start, and didn't spin at the same speed that it usually did.
I'd appreciate any help, this has been annoying for me weeks now. Thanks
It sounds like you are having a power issue and by looking at your specs I think I can see why. I believe that your PSU is under-sized for your current rig, you are actually under the recommended minimum of 550W just for your video card's specs. I know that number isn't from the manufacturer, but guru3d is typically right on when it comes to this stuff (Newegg however, shows a manufacturer number of 500W). Either way you are very close.
Also, are you connected straight to the motherboard's 3 or 4 pin connectors? Or are you connecting using molex connectors? Either way it may not be a bad idea to try out the other if you have a converter (i.e., convert the 3 or 4 pin to a molex then connecting straight to the PSU). If you are connecting to the motherboard now this well to eliminate the headers as the potential problem if it continues to occur.