CrossFire 4890 on an Intel P35 chipset?

[shangshang]

I have an Asus P5k that has the intel P35 chipset. It has 2 PCIE slots but the second one is limited to 4x. Right now I'm running one ATI 4890, and I'm thinking of possibly crossfire with another 4890, but I'm thinking that the P35 chipset will greatly limit the 2nd 4890.

Am I correct in my concern? Should I just forget about it?

 

[alyarb]

you are correct and should forget it. what CPU are you running? what game are you running that needs two 4890s?

 

[yh125d]

Yeah, with 4890xfire you're gonna want a highly clocked quad to really get all that it can do. If you have a highly clocked quad, I'd upgrade to a p45 board like a UD3P which will be 8x xfire, and pci-e2.0 so 4x the bandwidth of a 4x 1.0 slot. If you *dont* have a high speed quad, I'd hold off on the xfire til you upgrade to i7/x58

 

[Tempered81]

2 4890s in a p35 would work, but I would do like yh125d said and get a p45. x48 would be even better, and i7/x58 the best.

 

[shangshang]

for CPU, I have the Quad Q9450 running stock speed 2.66 Ghz. I've never overclocked it but I guess I could but I hate mucking around with oc'ing.

I'm happy with my system the way it is, but just thought with the prices of the 4890 dropping and will continue to drop even further, I'd experiment with Xfire. But as for a need to Xfire, there's really no need, other than perhaps re-play Crisis at 1920x1200 at max settings!

And no I'm not looking to spend "x58/i7" money so i can Xfire a 4890. However, I might consider getting a P45-based or X48-based motherboard provided they support DDR2 RAM!

Thanks for the input!

 

[KIAman]

You could do it but I've seen benches where a p35 loses out on average 35% performance compared to p45 or X38/48.

 

[Schmide]

It wins in power consumption?

 

[alyarb]

This is a great price for a great board and will give you not two, but three full speed pci-express slots.

http://www.newegg.com/Product/...x?Item=N82E16813186144

And in my opinion you should see what that Q9450 can do with stock voltages. 3.0 to 3.2 GHz I would assume. I also think you should get an aftermarket heat tower whether you overclock or not.

 

[apoppin]

Originally posted by: shangshang
for CPU, I have the Quad Q9450 running stock speed 2.66 Ghz. I've never overclocked it but I guess I could but I hate mucking around with oc'ing.

I'm happy with my system the way it is, but just thought with the prices of the 4890 dropping and will continue to drop even further, I'd experiment with Xfire. But as for a need to Xfire, there's really no need, other than perhaps re-play Crisis at 1920x1200 at max settings!

And no I'm not looking to spend "x58/i7" money so i can Xfire a 4890. However, I might consider getting a P45-based or X48-based motherboard provided they support DDR2 RAM!

Thanks for the input!

go for it!!

for $150 or so you will get a LOT more performance
- *less* than what you would get with 16x+16x PCIe CrossFire lanes, but enough to make a difference in frame rates over what you have now

and try for at least 3.2 GHz on your q9450 to unlock the potential of 4890 CrossFire
- after you do that, you might consider a X48 MB
-- BtW, i have a ASUS p35e X48 Mobo returned from ASUS RMA unopened for $90 shipped in FS/T right now [it is basically "brand new" rebuilt/recertified and can be flashed into the $300 ASUS "Rampage Formula" - 16x+16x PCIe slots]

 

[Sylvanas]

Don't bother with 4890s on a P35- thats a 16x 4x config and the 4x config is off the Southbridge through DMI- you'll be losing alot of performance that negates the point in spending money on another 4890. A single 4890 will do just fine however, so IMO either stick with 1 or get a P45/X48 for two.

 

[apoppin]

Originally posted by: Sylvanas
Don't bother with 4890s on a P35- thats a 16x 4x config and the 4x config is off the Southbridge through DMI- you'll be losing alot of performance that negates the point in spending money on another 4890. A single 4890 will do just fine however, so IMO either stick with 1 or get a P45/X48 for two.

Have you actually *tried* it in comparison to full 16X+16X CF?
i did
- you lose maybe 20% from "maximum" bandwidth potential

BUT ... You GAIN over 40% over what you have NOW
-look at it that way; it is *only* $150 for just sticking in a card and enabling CF

 

[alyarb]

tweaktown did a X48 vs P45 crossfire article. lost a lot more than 20% according to their data. but i'm just splitting hairs. i think buying a second gpu solely for crysis is retarded. he has the ideal single card system for the most part. next generation GPUs will be able to handle crysis. he can get a new GPU in the $200 segment 8-10 months.