Don't know how to help, it works like a charm for me. If it's any help my specs are:
i7 860 @3,6 ghz
p7p55d evo
8gb ram
2x MSI 750 Ti
2x Gygabite 750 oc
gtx 670
Corsair hx850
+latest drivers
+pciex 16 to 1x risers, powered
The 750's have a pciex power of their own while the powered risers don't do anything for my Ti's. They are just plain rotten.
Yeah my setup is pretty different.
Got three rigs with the same motherboard ( h61 pro btc ) , same processor ( cheap celeron ) ,4gb ram ,some old junk 40gb HD on each of them. Same power supply and risers.
Only difference is one of the rig is 6x 750ti's , the other two are 6x 750's.
The new miner work just fine on the ti's , and not on the 750's and it is the only difference between the rigs.