problems with multiple games

when im playing warcraft 3, about 5 minutes into each games, it exits to windows with this error...
------------------------------------------------------------------------
FATAL ERROR!

program: warcraft 3
exception: 0xC000001D (ILLEGAL_INSTRUCTION) at 001B:6F02C8A9
------------------------------------------------------------------------

.. or this error (mostly this one) ..

------------------------------------------------------------------------
FATAL ERROR!

Program: c:\program files\warcraft iii\war3.exe
Exception: 0xC0000005 (ACCESS_VIOLATION) at 001B:6F57E133

The instruction at '0x6F57E133' referenced memory at '0x00000008'.
The memory could not be 'read'.
------------------------------------------------------------------------

then when im playing battlefield 1942, about every 10 games or so, it just exits to windows and the program closes??

lastly on counterstrike v1.5 it just exits to windows as well, about every 1-2 hours i play it.

the reason ive posted these problems here is because ive contacted all of the companies' support options and nothing is helping me. really drivin me nuts that i cant play warcraft with my buddies! any help would be greatly appreciated =)