Need help finding RDRAM I can OC

I currently have an ASUS P4T533-C w/512MB Kingston RDRAM. The system is OCed to a FSB of 150 and all is well. I ordered two new 256MB sticks from Kingston just before they stopped selling them, but the ones I got would only run at the stock FSB speed of 533. I told them they were bad and sent them back. When I received a new set, it was the same deal. I could not go past stock settings with them. The markings on the sticker end in A01 and my current modules end in A00. I was told by Kingston that the ones sent me are newer than what I currently have. I guess they went with cheaper chips for the new revision.

So I currently have their earlier modules running at 1200 and like it this way. I was hoping someone could point me towards a manufacturer that I might have better luck with finding modules I can run along side my current ones.

Thanks

Robert