Upgraded to windows 7, games lag more?

Ok guys I don't know how to explain much of my problems but i can describe them sorry is just my way of organizing a sentence.-Fir's i use to play a game call Saurbraten on my Computer-* Even though it lagged every 20minutes* , and This is in windows vista. By the way i installed minecraft and i have 1.5GB RAM but is still lagged a little to much I heard that the graphics is not the part that is loading that much but something else rendering?Ok windows 7- i Upgraded yesterday, and i tried playing saurbraten it lags all the time can't move the mouse right etc....when i tried to play minecraft it said you need to update your graphics card i went to my Computer Properties device manager graphics and pressed update and Im in the latest version i also checked Direct X i have latest version (11)So i don't know what is happening help...BTW i got ubuntu can i run these things on that OS?

Did you mean 'Cube 2: Sauerbraten'? If I remember correctly, the game was released around 2004, or maybe 2005 - that was far beyond Windows 7 and even Windows Vista era. Most likely, the game has compatibility problems with both OS (it was Windows XP era, right?). Given that the game is an open source free game, I doubt if it will get updates to play on Vista and 7, the best OS to play it is still Win XP. So the best solution is probably to try playing the game using compatibility mode within Win Vista/7 (right click on desktop, properties, and choose 'compatibility' tab and choose Win XP - or similar commands). As for Minecraft, I don't think it is the same case, as it was a relatively new game, released in 2009. But maybe you can also try the same solution: run the game in compatibility mode and select Windows XP. In my opinion, XP is still the best OS for most games, even the newest games are still playable on XP and will most likely remain the same for at least one more yearAs for Ubuntu, both games do not specifically require Windows platform to run, so they may run on that OS, providing it supports Java applet. You might want to try. Given that Ubuntu does not draw resources as much as Windows, both games may run smoother. Good luck