ok well checked drivers they are up to date,screen starts flashing as soon as I go in world doesn't matter what sim I am on or wich viewer I use still happens my system specs are intel core 2 duo 3.00 4 gb memory with 2.94 useable gb 64 bit operateing systen windows 7 ultimate and I am using a Nvidia GeoForce 9400gt 1GB graphics card and I pefer to use firestorm viewer but have same problem on the sl viewer as I do on firestorm