Notebook onboard Radeon Xpress 1250 help

[Sweeper]

What the heck is the Radeon Xpress 1250 integrated GPU? Is this a form of PCI-E or just PCI? When I go to read it through GPU-Z it just says PCI. So is this just running off a PCI bus and using the (up to 896MB) of my system memory? The only description I have is (Up to 896MB ATI Radeon Xpress 1250 HyperMemory).

The system specs:

AMD Athlon 64x2 Dual Core processor TK-55 (1.8GHz, 2 x 256 KB L2 Cache)
ATI RADEON Xpress 1250 (integrated GPU)
4GB DDR2
160GB HDD
Etc....

[Big_Daddy]

It is built into the motherboard. It is not a card

[Sweeper]

I know it's built into the MB but what I'm asking is if it runs at the same speed as PCI-E or is it just run off the PCI bus at a standard 33MHz speed say like a PCI Video card in a Desktop.