Virtualdub2 can't capture at 60fps

[vigan1]

Virtualdub2 can't capture at 60fps GDI screen.
Do you know why ?

I put 60 fps at the CAPTURE > Capture setting.
And the status bar show 60.00 fps.

But it seems locked at 30fps when the capture start.
I even tested it on AMD ryzen 6cores 12threads and same thing happens.

Utvideo, Huffyuv, Magicyuv or x264 all caps at 30fps.
Can you help me.

EDIT : Fixed it's because I used gdigrab, don't use this use dxgi or opengl.