1900XT-X a waste for crossfire?

[glenimp617]

reading reviews it seems the xt-x gets down clocked when running in crossfire as the master card is an xt and not an xt-x

is this true, or can u clock (bios hack) the master up to an xt-x

Cheers!

 

[LoadsaMoney]

I thought they ran at their own clockspeeds.

 

[JonnyGLC]

If they do clock down, i'm sure you'd be able to clock the crossfire master card up to the XT-X speeds. Wouldn't be such a waste then.

 

[glenimp617]

Finally found it:

http://www.guru3d.com/article/Videocards/332/2/

Just wondering when I put my order in, if I should go for the XT or XT-X. I'd like to hear from anyone who has purchased an XT-X and crossfire to find out if they knew about the downclocking

 

[LoadsaMoney]

Well according to Hardocp which i quote :-

The Radeon X1900 CrossFire Edition is allows you to pair it up with an X1900 XT or XTX for dual card action. The CrossFire edition is based on the Radeon X1900 XT clock speeds (625MHz core and 1.45GHz memory with 512MB of GDDR3). Don’t fret though; you can indeed use this CrossFire card with the X1900 XTX. Remember that with CrossFire, you can use two video cards running at asynchronous clock speeds without one card “downclocking” to match the speed of the slower card. Of course, you can only render as fast as the card is clocked, but dual cards would still be faster than one XTX. The price is set at $599, and it includes the dual link DVI connector to allow high resolutions and refresh rates.

Im sure thats right as well, and that bit in the Guru article is wrong, as there was no x1800 XL mastercard for Crossfire, if you wanted to go Crossfire with the x1800 XL you had to buy the x1800 XT mastercard, and all it lost was 256mb of memory, so what you had was an X1800 XT, and an X1800 XL in Crossfire.

Come on Gibbo you will know for definate.

 

[fullfat]

ive also read that the 2 cards in xfire will work at their independant speeds

 

[daftVader]

I have a Crossfire and an XT-X... and damed if i can work out what runs at what LOL. All I know is they go like the clappers.

There may be a clue in the Catalyst Control Center: In the Overdrive settings panel there are only gpu and mem clock sliders for one card. In fact only one card is listed in the drop down box and that's the crossfire card. What's the point of having a drop down box with only the one card in it anyway?

The sliders default to 621 gpu/720 mem (the lowest settings on the slider) and go up to to 690 gpu/800 mem. I may have been lucky or this may be the norm, but I can run with both sliders at max settings (water cooled). Currently got them at 689/797 because that's what the automated clock configuration picked when i ran it. On air I had them stable at 689/761.

 

[S_D]

Hi there,

There's a crossfire FAQ on the ATI site and it does indeed confirm that crossfire will cards each run at their own speeds.

Simon