Fans go crazy when looking at websites

[Drummingknifes]

Hi, I'm not quite sure what's going on. Lately I've noticed that whenever I'm browsing regular websites suddenly one of my fans goes very loud. Which is pretty strange because I'm not watching anything too demanding (just some gifs for example). I have nothing open but Chrome with about 3 to 4 tabs.
I used Speed fan to check on the Rpm and snapped a picture. http://postimg.org/image/t1g553i4z/
Although right now its stating even higher, for the first fan it says its about 12500 RPM and the second one is 1563.
General specs of my PC:
MoBo: H61 M-E
Gtx 970
Intel I5 3340
8 gb ram
Windows 10 Pro
The case is a Corsair, Graphite 230T
For fans I have the stock fan from the case, I also have an extra fan attached to the top so that it pulls air from the inside to the outside of the case (can't remember the model, but its a corsair fan) and I have a CPU fan as well (not the stock one).
I've noticed this ever since I opened my PC to switch the orientation of the psu fan (had it pointing upwards instead of down to the floor). Any help? i really have no idea what's wrong.

 

[getochkn]

It should be pushing towards the floor and blowing all the hot air from the PSU out of the case, not into it.

If one fan gets loud, should be easy enough to figure out what fan it is.

Also if you have 3 and 4 pin fans mixed, it can create problems.

 

[Ok Go]

jesus 12k rpm. what are you trying to do with your pc? turn it to leaf blower? the only fan that i have able to reach 12k+ rpm is a 2.7amp 60mm JMC/Datech and that thing is louder than a vacuum cleaner.

either you're using industrial grade fan or your sensor is kaput.

 

[synphul]

Since it happened or you noticed it since turning the psu around, it might be that the psu isn't getting enough air if the case is on the floor. Restricted airflow could cause the psu to heat up and the fan to work harder. Unless it's a really unusual power supply, the vast majority I've ever dealt with blow air out the back. The large fan behind the grille on the top/bottom (depending which way you have the psu installed) is an intake, not an exhaust fan.

If the psu fan opening is facing down, it's drawing air up through the bottom of the case and venting out the back. If the fan's on top like it was, it's drawing air from inside the case and venting it out the back. It would be extremely difficult to get a psu to blow air into the case unless you opened the psu up and manually turned the fan backwards and remounted it.

Still a good idea to listen to the pc, try to get right up next to the tower and remove the side panel and try to pinpoint which fan is causing the noise while browsing. If you have a spare paper towel tube handy you can use it to isolate the different fans. Hold it up to your ear and place the other end near each fan (including down by the psu) to see if you can locate the source.