m9750 crashes while gaming

hi out there
i have a serious problem with my m9750 with 2x 8700m gt, running win7 32bit atm
When i play games after some time its stopping/lagging for a second and after that i can continue the game in most cases.. but when im playin Company of Heroes, same thing happens but after the crash my game freezes a few seconds, when i move my mouse... and after 10-20 times the laptop crashes
(i already used another mouse)

tried many things by now: tested maaaany different video drivers, updated system bios, downclocked the cards, put the cards out and cleaned everything, put silver arctic on them etc. and i dont think its a heat issue, both cards run at 87°C max while playing..

maybe a vbios update will help? atm i have these versions:
60.84.68.00.52 and 60.84.68.00.51
i thought the need same bios versions in sli but also read, that in the aw laptops they need to be different for master &slave?
can someone provide me the m&s bioses for my 8700's, only find single bios via google :/
i think i'm gonna try to change master &slave with new bios then

my warranty already ran out so i'm watching 2x7950gtx on ebay right now..but to be honest i would try anything to save me the money for them... i'm open for any suggestions

so i tried to keep my text short, but let me know, if you need more info

tyvm cheva

already did that and tried different os also (xp,vista,7 32and 64bit versions)

yeah, but i forget to mention: error comes only during gaming, benchmarks, gpu stress test etc. run without problems for hours

yap everything up2date. tried any kind of video drivers (original nvidia, alienware, from laptopvideo2go, modded drivers (omega, extreme g..). i dont have a cooler, but removed the cover plate and set the laptop higher, temps went down about 10°C after.

i will try the drivers later and put new paste tomorrow, hope it works. thanks for the tips

tried drivers and put on arctic silver 5 as showed in a how-to here in forum.. things went better but error still happens :/ maybe that gpu backing will help?^^

oh lol of course baking^^

it's been a while, i checked the thread.
error reporting is activated and im gonna check the dump file after the next crash.
did you solve your problem romes?

edit: laptop only freezes, no bluescreen, so i didn't get a dump file

only for a hour yet, but gonna do it overnight at weekend.
should i only test vram or system ram also?