I'm actually in single mode atm, I was having a weird issue where I could only hit 3d low clocks in single mode, pulled a card out, and now I can do 666/1622/1188 fully stable. Thats's on my 55nm card at 1.18v. I think my 65nm card isn't that stable....
Validation:
http://www.techpowerup.com/gpuz/ndcks/ I think I could do higher stable. I'll let you know!
Yep, I can, 1656 shaders. It's super chip!