4870x2 on a PCI-E 1.1 Bus

2008-09-21 22:57:12

#1

rammunition: Fully Loaded; +143|6128

ok,im quite interested in splashing some cash on this GPU, but have been reading that this card uses far more bandwidth than than any other card.

now according to GPU review.com this card uses 230.4 GB/sec in bandwidth and if im correct the 1.1 bus has a max of 250.0 GB/sec making the card just under the max bandwidth of the 1.1 bus. (correct me if im wrong)

http://www.gpureview.com/Radeon-HD-4870 … d-572.html

so should that mean this card would work without major decreases???
i know ati will push the card further with driver updates in the near future

also im wondering does anyone have a link to benchmarks for the ATi 4870x2 on both a PCI-1.1 board and a 2.0 board with the same configuration to see if there is a bottleneck or major decrease of any sort. there is nothing concrete atm on the 1.1 bus performance and is mainly just opinions. maybe one of you guys has a 1.1 and 2.0 board with this card and test it out if possible

also i know a rubbish CPU can bottleneck the card/computer but more intrested in the GPU on the 1.1 bus

2008-09-22 00:55:56

#2

some_random_panda: Flamesuit essential; +454|6657

I don't think the bandwidth will matter if it's lower than that of the motherboard.

That said, I'm just settling for a 4870, as my 6400 will still be bottlenecking unless I OC.

2008-09-22 01:04:20

#3

Bertster7: Confused Pothead; +1,101|6848|SE London

some_random_panda wrote:
I don't think the bandwidth will matter if it's lower than that of the motherboard.

That said, I'm just settling for a 4870, as my 6400 will still be bottlenecking unless I OC.

Will it though.

CPU/GPU bottlenecks are very misunderstood. Having a GPU that overperforms compared to the CPU is not such a bad thing. Lots of things that you want to turn on don't really affect the CPU time, things like AA (resolution is probably the graphics setting with the biggest impact on the CPU). The point of a good GPU is to be able to put high settings on in game, you can still do that with a CPU that is less powerful, since the processing occurs in different areas - though you may struggle with some CPU heavy games, but no more than you would with a lesser GPU.

2008-09-22 06:30:37

#4

max: Vela Incident; +1,652|6834|NYC / Hamburg

the 230GB/s quoted is the internal bandwidth of the memory. The bandwith that is used over the PCI-e bus will be a _lot_ lower. There is absolutely no problem running an 4870X2 over a PCI-e 1.1 x16 bus. Even a 1.1 x8 would do fine

_{once upon a midnight dreary, while i pron surfed, weak and weary, over many a strange and spurious site of ' hot xxx galore'. While i clicked my fav'rite bookmark, suddenly there came a warning, and my heart was filled with mourning, mourning for my dear amour, " 'Tis not possible!", i muttered, " give me back my free hardcore!"..... quoth the server, 404.}

2008-09-23 05:02:19

#5

rammunition: Fully Loaded; +143|6128

some_random_panda wrote:
I don't think the bandwidth will matter if it's lower than that of the motherboard.

That said, I'm just settling for a 4870, as my 6400 will still be bottlenecking unless I OC.

the 4870 seems the best option for the 1.1 bus atm tbh

max wrote:
the 230GB/s quoted is the internal bandwidth of the memory. The bandwith that is used over the PCI-e bus will be a _lot_ lower. There is absolutely no problem running an 4870X2 over a PCI-e 1.1 x16 bus. Even a 1.1 x8 would do fine

so is the internal memory bandwidth the bandwidth that is used by the 1.1 to communicate??
so how do i tell how much bandwidth a card uses???

max bandwidth on the 1.1 bus is 0.25 GByte/s and 2.0 is double that.

Last edited by rammunition (2008-09-23 05:10:18)

2008-09-23 06:34:37

#6

max: Vela Incident; +1,652|6834|NYC / Hamburg

internal memory bandwidth is the bandwidth of the of the bus between the GPU and the GPU memory. The PCI-e bus has nothing to do with it.

_{once upon a midnight dreary, while i pron surfed, weak and weary, over many a strange and spurious site of ' hot xxx galore'. While i clicked my fav'rite bookmark, suddenly there came a warning, and my heart was filled with mourning, mourning for my dear amour, " 'Tis not possible!", i muttered, " give me back my free hardcore!"..... quoth the server, 404.}

2008-09-25 05:06:09

#7

rammunition: Fully Loaded; +143|6128

max wrote:
internal memory bandwidth is the bandwidth of the of the bus between the GPU and the GPU memory. The PCI-e bus has nothing to do with it.

so what part of the card uses to the PCI E bus to communicate???
how do you tell how much bandwidth a card uses???

2008-09-25 05:41:35

#8

max: Vela Incident; +1,652|6834|NYC / Hamburg

https://images.anandtech.com/reviews/video/ATI/4870X2/sideport.jpg

however it doesn't need the theoretical 5GB/s up and down. A PCI-e 1.1 x8 slot will be sufficient to run the card to it's full extent

as to finding out to how much it really needs, ask someone with that card to run some tests for you

Last edited by max (2008-09-25 05:46:00)

_{once upon a midnight dreary, while i pron surfed, weak and weary, over many a strange and spurious site of ' hot xxx galore'. While i clicked my fav'rite bookmark, suddenly there came a warning, and my heart was filled with mourning, mourning for my dear amour, " 'Tis not possible!", i muttered, " give me back my free hardcore!"..... quoth the server, 404.}

2008-09-25 06:27:23

#9

rammunition: Fully Loaded; +143|6128

max wrote:
http://images.anandtech.com/reviews/vid … deport.jpg

however it doesn't need the theoretical 5GB/s up and down. A PCI-e 1.1 x8 slot will be sufficient to run the card to it's full extent

as to finding out to how much it really needs, ask someone with that card to run some tests for you

thanks for the diagram, though will wait before asking someone as this card has problems on the 1.1 and 2.0 bus as only half of it only works and the benchmarks for some people are lower than the nvidia 8 series card.

BF2S Forums 4870x2 on a PCI-E 1.1 Bus

some_random_panda wrote:

some_random_panda wrote:

max wrote:

max wrote:

max wrote:

Board footer