I recently bought AS2 and tested it on my laptop, works perfectly. Then I installed the game on my desktop pc and it is laggy even when there is nothing going on. The scrolling is jerky and whenever there is a alien basted the framerate drops. Any ideas?

Specs:
Win7 x64 pro
Intel i7 920
6 GB RAM
AMD HD 5850

Latop:
Win 7 x64 pro
Intel i5 450m
8 GB RAM
Intel HD / Nvidia 310 GTM

Tested with another laptop with only intel GMA card, seems the problem might be with AMD gfx card.

Have you tried changing the ATI drivers you are using? Or even just resetting the Catalyst control center settings.

I have lag as well on a Nvidia card, ran fine on my 2006 XP comp so I think it's an issue with newer systems.

I played the game's demo version and it ran a bit sluggish, but after changing VSync to 0 in AlienShooter.cfg... it is smooth as baby's bottom... try it out.

That fixed it right up, thanks.

LethalGoose, thank you very much!!!

thanks. I did this + based on the suggestion on the Steam forum for this game, since I'm on an Nvidia card I changed the Low Latency Mode to "On" for this game in Nvidia control panel > Manage 3D settings > Program Settings. Not sure which one worked but in any case the choppiness was greatly reduced. (still seems slightly there but that could just be my eyes :P)