is my GPU bottlenecked?

Vilsi

Honorable
Nov 29, 2013
92
0
10,660
hello i want to know if there is any bottleneck on om gpu
cpu: amd phenom II X4 965 Black edition OC 3,8 GHz max temp 42c
gpu: gtx 550 ti asus DC 1Gb
Psu:corsair tx 750 V2
MoBo:asus M4N68T-M LE

when playing assassin's creed 3 gpu load sometimes reach 99% but sometimes stays on 45-60%

thank you in advance