okay this is for anyone outta there who might find this usefull
the problem was that my counter strike source crashed after like 10 minutes and it was really annoying ... this soloution is not new but what i did was that i turned all my video settings to low but then the game looked horrible

i mean the ak was like the ak in the first ever counter strike

so i made all of the high except for the model and texture settings i left these for meduim
now its just a matter of time

high settings = crash after about 10 minutes
meduim settings = crash after about 1.5 hour
low settings = crash after about 4 hours
unknown settings = No crash

i dont know that settings yet .. if i knew it i would post it back here .. i hope this helped anyone