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Old June 19, 2008, 01:08 PM
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SKYMTL SKYMTL is offline
HardwareCanuck Review Editor
Join Date: Feb 2007
Location: Montreal
Posts: 13,641

Maybe I should put some information behind why I have an issue with this article. I am not calling it BS...I just want to furnish you guys with some info.

Please remember in all of this that P45 boards have TWO 8X PCI-E 2.0 slots when working in Crossfire.

PCI-E 1.1 transfers 250MB/s in each direction (up / down) per lane.
This means that at 8x (8 lanes) would be transfering 2GB/s and 16x would be transfering 4GB/s

With me? I hope so!!

PCI-E 2.0 was instituted and DOUBLED that rate to 500 MB/s in each direction per lane
That means that 8x transfers 4GB/s and 16x goes for a whooping 8GB/s

Still here? Good!!!

To put this into context, check this out:

PCI-E 1.1:
8x = 2GB/s
16x = 4GB/s

PCI-E 2.0:
8x = 4GB/s
16x = 8GB/s

Now let's come out with it shall we?

PCI-E 2.0 8x = 4GB/s
PCI-E 1.1 16x = 4GB/s

Wee what I'm saying?

Basically they are saying that a PCI-E 1.1 16x slot will bottleneck a HD4850 card.
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