Since I've had my Datapath VGA capture card, I've had some insight into the actual video modes for TGM and TAP. And they're not as straightforward as you might think: TGM1: H 15.738KHz, V 59.840Hz, 320 x 240 progressive TAP: H 16.165KHz, V 61.680Hz, 320 x 240 progressive What this means, is that all current MAME versions run TAP at an incorrect framerate (60fps instead of 61.68fps). For TGM1, the difference is negligible. If you wonder how this could slip by unnoticed for all these years; the answer is that the programmers assumed 60.0fps when writing the game timer routines. So on MAME, the game timers are correct: 8 minutes is actually 8 minutes. On the actual PCB, 8 minutes on the timer elapse in 7 minutes and 46.7 seconds of real-world time. This is a quite significant difference, and it's just been confirmed with stop-watch timing by colour_thief and DeHackEd. I've made an account at mametesters.org, but I can't file a bug until having waited 24 hours for approval. Consequences: all TAP MAME records are technically invalid due to having been played with 2.75% slowdown. Even when the video modes get fixed in MAME, it will be mandatory to play without "syncrefresh", unless you have a custom video mode (for instance with Soft15KHz). When the bug gets fixed, a new version of shmupmametgm will be compiled, and all old records marked with "speed bug" in the rankings.