There are ways but you don't have to lower your gfx..
You want to improve Performance i'm recommending these but if it's your first time doing it then read into it first. If you could post your PC specs i could probably give you more info.
+ Overclock CPU - Can be done in bios or many programs to download
+Overlock GFX - if you have ATI i reccommend ATITOOL
+ Overlock Ram - Ram optimizer
+Use a differnt DX level.. I think it's matt_dxlevel 7 or something you will have to look it up
+lower all settings in the gfx panel
+HEAT has a major part in your system check your heatsink give it a clean and replace the heat paste.. doesn;t sdounf like much but it always helps mine!
I can give you some more tips... what are you having trouble with GFX performance, internet performance or just general running speed?
If you give me your computer specs a small upgrade or just software upgrades may be needed
Ip i helps +Rep plz thankyou x x
