I have FPS problem HELP

doesn’t matter which settings i use, i always get 13 to 21 fps. what should i do? I even though i disable all addons and every map, i still get same FPS .

all of my drivers are up-to-date.

however, i don’t get any fps drops in other source games. only in GMod(original).

my system:İ5-3210m 2.50ghz
4gb ram
610m nvidia graphic card
windows7 ultimate 64bit
i know my card is bad but i can play farcry3 idont have fps problem but in gmod so low please help me.

sorry for bad english.