Anybody know about computers?

[Merlin]

As others have said, more info is needed, but without knowing more, this is my $0.02...

It doesn't sound normal to me unless it is a laptop. A laptop doesn't have much room to breathe, so they tend to get hot and need a lot of cooling, particularly when doing anything with a lot of number crunching, 3D graphics, or high resolutions. Since they only have tiny fans, those make a ton of noise when running full speed.

If you're using a desktop PC, then a lot of fan noise is not normal. Most retail systems should never get too loud. If they do, then it's likely that the CPU is overheating. That could happen for a number of reasons, but a loose heat sync is a typically the culprit there (they sometimes get loose due to jostling in shipping). Alternatively, the CPU cooler may be too small for the CPU and it has to run at full speed to try and keep up. But that is also unlikely since most retail PC's run lower-end CPUs that don't generate a ton of heat and for higher-end systems, manufacturers tend to match the CPU cooler to the TDP (temperature rating) of the CPU.