New PC, variable fan speed - gotta be CPU fan as already mentioned changing speed to provide extra cooling when the CPU heats up, usually when it's getting busy.

One option is an aftermarket heatsink that is physically much larger than the one you have which in turn uses a large diameter slow revving fan. The smaller a fan is, the faster it needs to spin in order to move sufficient air to cool the CPU - faster revving=more noise.

As this is a new PC I would advise talking to the supplier to make sure you don't void your warranty. If it is a "white box" assembled by a local PC supplier this shouldn't be a problem, OTOH if it is a "name brand" I doubt you'll find much sympathy.


--=-- My credo: If it's worth doing, it's worth overdoing - just ask my missus, she'll tell ya laugh --=--
You're only paranoid if you're wrong!