Question / Help Overwatch frame drop just by opening OBS Studio

[TACC]

Specs:
i7-3770k
ddr3 8gb
obs and overwatch is running on ssd
Elgato HD60 is plugged on.

Things i have tried

1.Changing bitrate from 3000~2000
2.switching encoder from x264 to nvec h264
3.CPU usage from Very fast to Ultra fast

problem is just as this title.

I was planning on streaming using two computer as different spectator.

one as main screen using elgato to hooked up to this computer, second is 3rd person's view by switching to overwatch that is running on this computer.

weirdly overwatch starts lagging (Dropped frame) just by turning obs on.......

is there any flaw i made in my setting?

any suggestion and help will be appreciated.

Thankyou!

 

[xxAssassin349]

OBS uses your GPU to render frames and composite the scene together. This will use up a bit of GPU.

Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 814 (10.4%)

To fix this problem, reduce GPU usage by lowering in-game settings or capping your frame rate.

 

[TACC]

So.. .
I guess in order to have maximum performance on my gpu,
Should i use x264 to render video for lessen my gpu load by not using gpu on obs?

Or just stick with my setting and lower the quality of ingame overwatch?