I finally got around to giving DosBox (0.65) a real tryout. You guys are doing great work. 😀

I tested the freeware releases of Tyrian2000 and Apogee's Stargunner. Much of the time, emulation is great, with smooth operation and no choppy sound. But Tyrian gameplay slows to a crawl in the very first level whenever there are translucent background cloud tiles present. The more cloud, the slower things get. It's not just the translucency, but turning down detail so the clouds go solid does make a difference.

I tried a lot of different settings via Dfend without any luck. Turned off scaling, tried different rendering methods, different CPU modes, different joystick types, the works. Tried shutting down Explorer, but it didn't help. Running DosBox direcly didn't help either. I'm not close to overloading the computer--turning up cycles will steadily boost performance in the slow areas until it's acceptable, but the moment the clouds or other sources of slowdown are offscreen, the game speeds up to unplayability. Dropping frames doesn't fix the underlying problem. Throughout all this, sound never became choppy or excessively slow; given that it looks like a display problem of some sort, I didn't bother testing with sound off.

I saw something similar when I tried Stargunner. Normal performance is smooth and reliable, but when the game tries to put up a Star Wars-style scrolling words introduction, it runs at a snail's pace. So perhaps it's related to how my computer is handling certain types of parallax-scrolling overlays?

Since I'm just starting out with Dosbox, I don't know if I'm using it properly. Many guides are out of date with the 0.65 settings. I used around 5000 cycles, no frame drop, along with Up/Down of both 500/20 and 500/500 (I don't actually know what this last setting is for).

CPU is an Athlon64 3200 on a DFI Lanparty nForce3 board with plenty of RAM. WinXP/SP2. Radeon X800XL AGP, using fairly old drivers (I never switched to the .NET releases). Other posters here have said they have Tyrian running fine on slower systems, so I'm wondering whether it's a machine-specific conflict, a new issue with 0.65, or just bad settings. Any thoughts?

false_dmitrii