That's nice. They probably added a new "strap" so that the PCIe frequency defaults to stock once you reach 333MHz, but there is a catch:
We were able to reach 355 x 7 on E6300 using SATAII HDD and 420x7 with IDE HDD.
So if you aim for 400-ish you have to have an IDE HDD. Then again, 355x9 is not that bad either for people not trying to squeeze the last MHz out of their CPU.