intel 875pbz socket 478 question

[lancer]

http://www.intel.com/support/motherboards/desktop/d875pbz/index.htm

I have the intel 875PBZ socket 478 board running a 2.8 P4 Northwood HT chip..
the intel site (link above) says it will run AGP4x and 8x

thus

AGP 3.0 (4X & 8X Speed at 1.5 and 0.8 Volt Only)

now I have an nvidia 5600fx card in at the moment. I am fairly certain that this was an AGP4x card. I'm looking to upgrade to the X1950 Pro AGP when it comes out which is an 8x AGP card. if I'm running the 5600fx, then I should be okay right? as if its running AGP 4x already, then the board is already 1.5 or 0.8 volt so 8x AGP should be fine, right?

does my logic track properly?

 

[lancer]

thanks for the answer re: the 5600fx. that means I'm safe on that point.

in actual fact both powercooler and gecube are producing an AGP version of the 1950, it's been announced on quite a few sites and is due this month.