Windows 7: USB mice freezes, Unplugs/replugs, works on other computers.

Couple of months ago I built a new computer from a scratch.
My Logitech G400 worked fine for like month and then it suddenly started freezing but not losing power( light still on ) Switching to another USB port fixed it for a while until only Rebooting made it unfreeze again.

My first thought was that the mouse is at its breakingpoint which felt weird because it was only 4 months old and worked perfectly with my old PC.
I gave it to my brother to test and he is still using it after 2 weeks of no freezing.



/I took my old Razer Diamondback 3G and used it pretty long time with no problems, until recently it started to unplug/replug itself for 2 sec at increasing interval each day./EDIT: This might be just coincidence as the mouse was old. need to test it on other computer.

Now I'm using Microsoft Basic optical mouse v2.0 Which is working fine.

I've tried googling up people with similiar problems but havent found a fix.
I have also deleted and reinstalled Drivers for both mice but nothing changes.

EDIT: I have USB headset that works fine in every port.

Sorry for my bad english, not a native speaker.
Thanks in advance!

Shameless bump.
+ more info

I'm actually thinking that the Razer problem is just the mouse being old.
So I took the G400 and tested it again. It froze again after playing for hours of minecraft without problems. It froze only after I started playing League of legends and other more "heavy" games in fullscreen. Could that have something to do with it?
(I left computer on the whole night @ desktop and mouse worked fine in the morning)

would appreciate any insight. thanks.