Weird lag

[Morbid Angel]

For some odd reason my blood flashes and tracer fire on my rounds stoped working a few weeks ago even when they were set to on. So I decided to do a cvar_restart and now they work fine. Problem is, now i get weird lag whem im around multiple people. Its fine when im far away from groups of people, fighting one on one for example, but once i join a large fight it starts lagging. I've never had this problem before the cvar_restart, and play with all settings on default (except controls of course)

 

So the question is, If ive always played with default settings, with no lag problems, why would doing cvar_restart (which is suppose to revert to default game) cause me to lag. How can i fix this?

 

Oh and I logged onto Return to Castle Wolfenstein to test my connection, and its the same its always been, works great on that game. So I dont think its my connection.