Playing some Duke Nukem 3D via eDuke and was surprised to see it's basically unplayable on my machine with vsynch on. Framerate is all over the place and choppy as heck. This is on a modern gaming PC (mid-grade but still).

Just wondering if it's an eDuke "thing" or if there's a way to fix it.

Have you tried one of the newer builds? Maybe a 64-bit version if you are using a 32-bit one (and vice-versa)? People have been reporting some success when changing a build. Just remember that saves might be incompatible across different builds (at least they were to me, last time I used eduke32.)

http://dukeworld.duke4.net/eduke32/synthesis/

I didn't know there was a 64bit version! I downloaded the latest file on that page and I'll try it. Thanks!