x800xl memory clock "whats up???"

[Triple B]

dorking around in catalyst panel tonight and notic under help\information center (where you can look up drivers, serial numbers, versions and the like) i see that my memory clock is listed at only 493 MHz.
all the literature from ati says the gpu is 980 MHz, WHAT GIVES???

my core clock is listed as 398 MHz, ati says 40MHz so thats close

can anyone explain, help, check theirs? it is setup totaly stock, just installed with drivers in the box

bios date is 11/24/04
driver package v. 8
catalyst v. 4.1
catalyst control center 1.0.1

thanks

 

[Lonyo]

It uses DDR memory.
The D in DDR stands for double (data rate), so you double the "raw" clock of 493MHz to get the speed it is effectively working at, which gives 986MHz effective speed.