Why does my T-Bird 1333 not post at 1333?

Hi

after having finally got my CPU to work I have the following problem: The TB only posts at 1000 Mhz, which would be 5*100*2= 1000. But why the heck can't I change to 133 FSB, I mean I have bought a 1333 FSB 266 CPU...everytime I go higher than 101*2 FSB my PC won't post at all, just a black screen.

My config is:

AMD Thunderbird 1333
Abit KT7A
256 MB PC-133 RAM
Creative GeForce2 GTS

So what could I do in order to make my PC post constantly. After having changed any settings in the BIOS and the PC reboots, nothing would happen, just a black screen. Sometimes it boots sometimes it doesn't.

So??? Any help is welcome...
Marc

THis is a known problem with those tbirds and the 266bus. The Abit was not supposed to have these probs.

Mine posted like that on my KT7A Raid at first boot. Then I changed it to user defined 10x133 loaded windows then started upping the fsb till I hit 1628 where I am running now.