I experienced some strange behavior recently.
I have groovyMAME setup on my 320x240 CRT with crt-emudriver and I noticed when I started up Area 51 that it was laggy and very choppy, but I thought nothing of it as I changed versions of MAME and was using old ROMs, and I'm probably going back to my older version anyways.
However when I was doing some setup on it I had it hooked up to my HD monitor via HDMI and when I ran Area 51 just to test something out, I noticed it was running fine.
Then I tried again on my CRT and yep, it was choppy and laggy.
So my question is - is there some setting that is making it run choppy when it loads up in the CRT resolution?