Irregular gpu usage

[alexand07]

Gpu usage goes up and down up and down from 64% to 100%, its never constant.

I just upgraded my gpu from a gtx 550 ti to a r7 265 but Im having trouble with the framerate, it kinda feels there is a cap because in the witcher 3 (eurogamer console settings) the framerate goes from 23 to 31 max , 34 to 42 max in far cry 4 (high settings) and 27 to 43 max in gta v (eurogamer console settings). It doesnt matter if the scene is demanding or not, the framerate dont go higher than the numbers stated above.

This is the graph of the typical gpu usage after playing the witcher 3 for an hour, it goes from 64% to 100%:

http://s1078.photobucket.com/user/chapapa07/media/usage...

The resolution I use is 1080p, vsync is off and the driver is up to date.

Specs:

I5 4570 3.2 GHZ
MSI H87-G43M
2X 4GB Corsair Vengeance
XFX r7 265 Core Edition 2GB
Wester Digital Caviar Black 1002FAEX 1 TB
OCZ Fatal1ty 550w
Windows 7 64 bit

[don_svetlio]

might be a PSU issue.