4850/70 on 975x mobo

[muppet]

hi

i was thinking of getting 1 or 2 of these but my 2nd pci ex is only a x8.
does anyone have one of the above cards running on a 975x mobo and is there enuogh bandwidth in pciex 1.0a to run these babies at full speed

cheers

 

[RavenXXX2]

One card perfectly fine, two cards will result in a large performance drop due to the slower speed PCI-E slot.

 

[ACESHIGH]

OP grab single 4870 or if you can wait and want more performance then wait until approx August for the 4870X2 and September for the 4850X2.

 

[MagicBoy]

One card perfectly fine, two cards will result in a large performance drop due to the slower speed PCI-E slot.

Hmmm, not sure about that.

P35 runs 16x and 4x, 975x 8x and 8x IIRC. Swings and roundabouts - I'd be surprised if there's more than a couple of percent in it.

4870X2 would be a better long term solutions as the PCI-e bridge is on the card.

 

[muppet]

hi
thanks for the input peeps . so if im only using one card (4870x2) will the card use all 16 lanes or will it just use the 8 that its plugged into

cheers

edit: One Primary PCI Express* x16 (electrical x16 or x8) bus add-in card connector
One Secondary PCI Express* x16 (electrical x8) bus add-in card connector
One PCI Express* x16 (electrical x4) bus add-in card connector

magicboy just got this off the intel website does it mean i have a x16 and a x8 slot

 

[MagicBoy]

hi
thanks for the input peeps . so if im only using one card (4870x2) will the card use all 16 lanes or will it just use the 8 that its plugged into

cheers

edit: One Primary PCI Express* x16 (electrical x16 or x8) bus add-in card connector
One Secondary PCI Express* x16 (electrical x8) bus add-in card connector
One PCI Express* x16 (electrical x4) bus add-in card connector

magicboy just got this off the intel website does it mean i have a x16 and a x8 slot

Depends on the board - doubt you've got a 975x board with three x16 connectors.

You'll likely have two physical x16 slots, but they don't both run all 16 lanes. With one graphics card you'll get all 16 lanes in the primary slot, the secondary slot running 4 lanes for other devices eg a RAID card/Soundcard etc. Stick two ATI graphics cards in and enable crossfire and it reassigns both x16 slots to 8 lanes each on the 975x. The later P35 (which i have) runs the primary at 16 lanes and the secondary at 4 lanes. 8 lanes isn't exactly slow - 2GB/sec (That's gigabytes) which is the same as ye olde AGP 8x.

The ATI X2 cards have an extra PCI-e switch chip on the card which talks to the motherboard at x16 then the two GPUs run off the switch at x16. Using this method the GPUs can talk to each other directly at full speed without having to go via the motherboard chipset.

Having used crossfire on a couple of x1950 Pro's on a P35 board I'd personally take the X2 route next time - less hassle. I'm currently on a single 4850 which has more than enough performance for the moment.

 

[psychas]

upgrade mob first leave gts(is it 512?) alone save money upgrade cpu if you gts is 512 then save again and then upgrade on a screen(if you have 19 inch u need atleast 22 ) and then gpu

 

[muppet]

hi

its a gts640 and i already have a 24 inch monitor . the gpu sruggles a bit on some games @ 1920x1200.
i was going to upgrade gpu this time to see if i can get another 12 months out of my cpu / mobo .

cheers

 

[psychas]

then go for gpu at taht res gpu botelnecks more then cpu i think