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Ryu Hayabusa

PCI X vs PCIE 2.0

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Okay, so i'm in the process of building a new computer and i'm going to update the Test Bed in my sig for the Ol' Lady. Now the Board thats on it is the ASUS A8N-SLI that has 2 PCIE x 16 slots. Now this where my brain has failed. blush3.gifI know that PCIE 2.0 is backwards compatible but what are the drawbacks of running a PCIE 2.0 card in a PCIE slot. My google-fu is weak today and I cannot find the info out there. dunno.gif Please help the moron that is me.

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Okay, so i'm in the process of building a new computer and i'm going to update the Test Bed in my sig for the Ol' Lady. Now the Board thats on it is the ASUS A8N-SLI that has 2 PCIE x 16 slots. Now this where my brain has failed. blush3.gifI know that PCIE 2.0 is backwards compatible but what are the drawbacks of running a PCIE 2.0 card in a PCIE slot. My google-fu is weak today and I cannot find the info out there. dunno.gif Please help the moron that is me.

Other than compatibility none that I can think of. AFAIK there aren't any cards that are bottlenecked on the PCI-Express 1.0 bus. Your title is a bit misleading though as this doesn't have anything to do with PCI-X.

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No drawbacks, but from the (limited) info I could find online, and using some probably extremely flawed logic, you can expect maybe like a 1 or 2 percent performance drop when using a high end card in a 1.0 slot rather than a 2.0 slot. The reasoning:

 

PCIe 2.0 has a bandwidth of 500 MB/s, and 1.0 has a bandwidth of 250 MB/s. I'm guessing that if you can compare two cards in PCIe 2.0 slots, but run one of them at half the bandwidth, then it should mimic the comparison you're after, 1.0 vs 2.0. This article does just that, running a 5870 at 16x, 8x, 4x, and 1x. Comparing the 16x to the 8x "should" be what you're looking for, and according to those graphs, the performance drop is only a couple percent at the most, for a fairly high end card.

 

Hope that helped

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No drawbacks, but from the (limited) info I could find online, and using some probably extremely flawed logic, you can expect maybe like a 1 or 2 percent performance drop when using a high end card in a 1.0 slot rather than a 2.0 slot. The reasoning:

 

PCIe 2.0 has a bandwidth of 500 MB/s, and 1.0 has a bandwidth of 250 MB/s. I'm guessing that if you can compare two cards in PCIe 2.0 slots, but run one of them at half the bandwidth, then it should mimic the comparison you're after, 1.0 vs 2.0. This article does just that, running a 5870 at 16x, 8x, 4x, and 1x. Comparing the 16x to the 8x "should" be what you're looking for, and according to those graphs, the performance drop is only a couple percent at the most, for a fairly high end card.

 

Hope that helped

 

 

Yes that helps alot. I was worried a 9800 would be bottlenecked but it appears that it will be just fine. thanks.

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Yes that helps alot. I was worried a 9800 would be bottlenecked but it appears that it will be just fine. thanks.

 

a 9800 wouldn't even bottleneck a 8x pcie slot.

 

pcie 2.0 was just another way for the video card manufactures to increase their prices without really giving you anything in return.

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a 9800 wouldn't even bottleneck a 8x pcie slot.

 

pcie 2.0 was just another way for the video card manufactures to increase their prices without really giving you anything in return.

 

To be fair, workstation graphics cards make plenty use of the enormous bandwidth use. And gaming graphics cards had no reason to stick to PCIe x16 when everything could just step up to 2.0.

 

If that makes any sense.

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