GPU 2, GpuMiner dk2an0 failed -4
Managed to get rid of it setting the virtual memory to...
50 GB ?!?!?!?!

What the hell are you doing with 50Gb ? Opening a a porn site ?

Some features still don't work and crashes the rig (GPU clock and setting the -h value).
Nice speed increase 10-20%

The same amount of memory that is allocated in the gpu memory and used for computations must be duplicated in virtual memory.
So for multi-gpu rigs it is huge.
-h option works well, check what you are doing ...