Question Gpu usage Jump

[Hvvno]

So just recently upgraded graphics card from old gaming pc and waiting for processor and motherboard to come but in the image is the graph of me playing sekiro at 1650x1050 at max settings http://imgur.com/8PdXZwr

Why is it jumping from 0-100 then from 100-0?
Is it because out of date drivers, gaming from external HDD, bottlenecking cpu or what is it?

Specs:
Graphics: Amd rx470 sapphire nitro+ OC
Cpu: intel i3 550 3.2ghz
Motherboard: Acer veriton m490g
Ram: not sure
Psu: thermaltake toughpower XT 850W

 

[rgd1101]

cpu usage?
could be cpu issue

what the ram?

 

[Hvvno]

8GB ddr3

 

[Hvvno]

cpu usage?
could be cpu issue

what the ram?

GPU usage not cpu


And 8gb ddr3

 

[rgd1101]

GPU usage not cpu


And 8gb ddr3

I mean we need cpu usage.
can't just look at 1 components to know whey you having system issue.

 

[Hvvno]

I mean we need cpu usage.
can't just look at 1 components to know whey you having system issue.

It’s like always at 60-90%