Hi. I have posted about this problem before. I thought it had gone away but it is just a random thing.
When the pc starts up it makes a loud whirring noise, not just whirring like a fan running very fast, it sounds sort of like a metallic noise,
hard to explain really.....Anyway, It seems that this mostly happens if the pc has been switched off for 24 hours or more, but even then it doesn't happen every time.
I took the tower out of the cabinet and placed it on top of the cabinet so i could take the side of the case off when i started it up and try and pinpoint which fan is making the noise.
As long as the tower stood on top of the cabinet and i was ready to locate the noise it didn't make that sound. Weird...I know. After about 2 weeks i put it back in the cabinet and it did it again, and has done it randomly ever since.
I always keep the inside as unclogged with dust as possible. There is plenty of room on all sides of the case to allow for good air flow.
When i log into windows and the desktop has fully loaded the noise in question slows down and stops and then sounds normal.
I have had the PC for about 5 years and the graphics card and PSU for about 1.5 years.
In 'Speccy' the CPU average temp says 50 degrees C. The motherboard temp says 32 degrees C.
Don't know if any more info is needed? It is just really annoying as i can't locate which fan is doing it.
Also when i run Skyrim the vid card seems to have to work way too hard. (I do run quite a few mods on the game though). But Max Payne 3 runs and there is no noticeable difference in the sound. I doubt if the gaming part is relevant but thought i would put it in just in case.
Any help would be much appreciated.