175/200 combo possible?

[Aplek]

Any of you know the right combo or program that would allow your G400 to oc to 175/200? I could get it at 180/200 but push the system clock at 400mhz (2.5, 2.25, 2.5 multiplier) and it would hang in the middle of the 3dmark 2000 test.
I wonder why MGA Tweak doesn't have a 1.75 multiplier?