Sped up video extremely laggy/choppy. What to do?

So, I use the free version of DaVinci Resolve as I am not paying £225 for editing software, and the sped-up video is surprisingly choppy/laggy. I have no idea what to do about it.

PC SPECS:

GTX 1060 (3GB VRAM)
Intel Core i7
16GB of RAM

If anything else is needed, let me know. Also, again, I am not paying £225 for editing software.

Thanks

Do you have Show All Video Frames checked in the Timeline Viewer menu? Is it possible your system just can't keep up with playback?

Does it export OK?

Since you managed to do a speed up, that means you don't need to buy 225 GBP editing software (it's quite normal not to pay for editing software, I agree).

Try quarter resolution playback.

AFAIK, optical flow is not available in the free version. So, I'd suggest you switch retiming to Blend and hope for the best. Or you stick to speeding up at integer values, like 2x, 3x etc. and switch to Nearest.

For me, two or three features alone would be enough reason to buy Studio. Speed Warp is among them.

Your 3GB version of the GTX 1060 is also a possible problem.