Crossfire Question?

[me/2]

I'm currently running a HIS IceQ3 Turbo 512MB X1950 Pro on a Gigabyte
GA-P35-DS4 Rev 2 motherboard wiht an E6750 Core 2 Duo 2.66 GHZ
(running at 3.2GHZ) CPU and 3GB of PC6400 DDR2 RAM. This is running XP
Pro SP2.

A friend of mine has the identical graphic card and is willing to give
it to me for free since he's updating to the X3870. Even though the
P35 chipset only supports PCIe at 4X on the second slot would there be
much benefit to adding the second card. A new motherboard with X38 or
newer chipset is in the plans for after the first of the year so if
there's not much benefit or if there could be issues with the
different PCIe slot speeds I can just stash the card until I get the
new motherboard.

Thnaks for any insight or links to articles that cover that issue.

me/2

 

[First of One]

At the time of this article (May 2007), Crossfire support on the P35 was not
immature. Performance boost with Crossfire was between 20% to 50%.
http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2995&p=4

Keep in mind you need CCC to load at Windows startup for Crossfire to work.

 

[First of One]

Err, make that "Crossfire support on the P35 was not *mature*..."

 

[Ed Medlin]

I'm currently running a HIS IceQ3 Turbo 512MB X1950 Pro on a Gigabyte
GA-P35-DS4 Rev 2 motherboard wiht an E6750 Core 2 Duo 2.66 GHZ
(running at 3.2GHZ) CPU and 3GB of PC6400 DDR2 RAM. This is running XP
Pro SP2.

A friend of mine has the identical graphic card and is willing to give
it to me for free since he's updating to the X3870. Even though the
P35 chipset only supports PCIe at 4X on the second slot would there be
much benefit to adding the second card. A new motherboard with X38 or
newer chipset is in the plans for after the first of the year so if
there's not much benefit or if there could be issues with the
different PCIe slot speeds I can just stash the card until I get the
new motherboard.

Thnaks for any insight or links to articles that cover that issue.

me/2

I am not sure about Crossfire, but with Nvidia's SLI it makes no difference
at all if you use the 16X slots or 8X slots as long as the primary card is
in the 16X slot. I had a problem with a particular case with an 8800GTX in
the bottom 16X slot not having proper ventilation. I moved it up from there
to the 8X slot just below the 16X slot and it worked perfectly. There is not
a single digit loss in 3dMark 06 or any other benchmark between the two.
With Nvidia's SLI, the performance increase from a single 8800GTX is about
35-40% and I would expect that Crossfire should be about the same.


Ed

 

[First of One]

Of course, on the P35 chipset, the second slot is x4, not x8.

As the Anandtech article shows, Crossfire performance on the P35 trails that
of the i975, which has effectively dual x8 slots. Still faster than a single
card, though.

 

[me/2]

:>At the time of this article (May 2007), Crossfire support on the P35 was not
:>immature. Performance boost with Crossfire was between 20% to 50%.
:>http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2995&p=4
:>
:>Keep in mind you need CCC to load at Windows startup for Crossfire to work.

I've been using the Omega drivers with the ATI tray tools for years
now. I notice that ATT has an option for Crossfire with 2 settings,
"Apply at startup" and "Enable CrossFire". I would hope this is all I
need.

Guess I'll find out next week when he brings the other card over. He
was one of the lucky ones that got a 3870 from Newegg before they ran
out and raised the price. He will be getting it next Monday or
Tuesday.

Thanks for the info. It looks like it won't hurt to go ahead and
install it now. Since it's free any performance gain at all will be
worth the price.

me/2

 

[First of One]

I don't recall seeing the Crossfire options in ATi Tray Tools the last time
I used it... Hmm, maybe I will try the latest version. Can't wait to ditch
the pathetic CCC.

 

[JamesH]

ATI Tray Tools, look under Hardware for the Crossfire option. It worked just
fine for me with 2x 1600xt.

 

[First of One]

Yeah, looks like it was added in a recent release. Last time I tried it was
about a year ago.