[PLUG] AMD 760MP vs. 760MPX chipset?

[Alex Daniloff]

Hello Linux folkz,
Could somebody from the experienced Linux server 
builders help me to solve this dilemma.
I have a task to build Linux DB server with SCSI raid.
I has to be a pure DB server without any fancy graphic
and sound stuff running in run level 3 all the time.
I have tho motherboards on my hands.
Tyan Thunder K7X S2468UGN AMD-760MPX chipset
and Tyan Tiger K7 S2462UNG AMD-760MP chipset.
Which one is the best suited for a such task?
I can't tell the difference in depth between
MP and MPX chipset, but the board with MPX has
two 64bit (3.3v and 5v) at 66 MHz PCI slots, MP has
five 64bit 5v at 33 MHz PCI slots.
Do modern PCI RAID controlles really support 66 MHz
PCI bus or it's just a marketing bluff?
Thank you in advance for any advises.

Alex