Starcraft runs choppy

[okeee]

win xp
AMD Athlon 64, 3500+
1 GB RAM
Geforce 7900 gt
starcraft 1.15.2

Starcraft plays smooth mostly (singleplayer game) , but frequently it runs choppy for a few seconds. Even when other programs are not running, and it's the same if i use the starcraft disc or not. Why is this?

 

[Executor Keldain]

What ISP do you have? Do you have a 56k Modem, Cable, DSL, Highspeed? Have you updated all of your drivers?

 

[CerebralChain]

Have you tried re-installing SC? And is it "choppy" only when you're online?