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a_anis3000Flag for Egypt

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Combining PCI Express 2.0 card with PCI Express 1.0 slot

I have recently replaced my old Geforce 8800 GTS 320mb with Geforce GTX260 896MB. I am happy with the performance boost my games gained particularly Crysis which is one of the most graphic intensive games. My only concern though is that the card is attached to PCI express 1.0 of a 1 year old motherboard (XFX Nforce 650i Ultra) which could be a bottlenock since the new VGA card is PCI Express 2.0. Depending on the impact and the performance gain in upgrading to PCI Express 2.0 I was wondering if there is a pressing need to change my current motherboard

Thanks in advance

PS: Details of my system are listed in my profile
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Callandor
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PCI Express 2.0 doubles the transfer rate of each lane, but the PCI Express bus is almost never a factor.  Most performance cards have huge amounts of DDR3 RAM onboard because the transfer rate is so much faster accessing the card's RAM than main memory.  If your game has large textures that exceed the card's onboard memory, then the PCIe bus will be used to transfer that data, but it will be slow compared to onboard.  Even doubling that transfer speed is still much slower than RAM on the card, so don't worry about it.
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What about the ongoining data transfer between CPU and the graphic card? The game is processed by both graphic card and CPU, in fact there are many games that are both GPU and CPU intensive so a faster CPU will boost performance as well. Data is constantly transferred back and forth between these two components through the PCI Express bus. So perhaps there is a performance gain  in doubling the transfer speed (ie upgrading to a PCI Express 2.0) as both components will wait less for data to arrive.





Most games work best when this data transfer is minimized.  I have not seen any benchmarks that indicate you are better off with a PCIe 2.0 vs PCIe 1.0 slot.  The overwhelming factor is the GPU design: clock speed, size of VRAM, number of pipelines, etc.  If you can find a review that says the slot version makes a big difference, I would like to know about it.  See http://forum.beyond3d.com/showthread.php?t=45229 for a discussion of this.
>>>If you can find a review that says the slot version makes a big difference, I would like to know about it.<<

I did a bunch of google searches for PCI Express 2.0 reviews, I only found this Tom's Hardware
benchmark which looks fairly rfecent

http://www.tomshardware.com/reviews/pci-express-2-0,1915-10.html

with most benchmark test like 3DMARK the difference between PCI Express 2.0 and 1 is subtle in terms of games I didn't see much difference in the test with mainstream card like the ATI 3850, but its more pronounced with high end cards like the Geforce 9800 GX2. in the latter test (page 10) some games showed performance gain, for example Call Of Duty 4 scored 131.5 FPS and 122 FPS with PCI Express 2.0 and PCI Express 1.

This suggest that some games with larger texture might benifet from the extra PCI bus bandwidth
and  likely the difference will be more evident with future games and next generation cards

So perhaps futureproofing-wise I should upgrade to a PCI Express 2.0 motherboard



Yes, that's basically what I was saying: you would need large textures to force the card to use main RAM and thus pass it over the PCIe bus before you noticed any difference.  As far as future proofing, I have learned that it is not as good a strategy as one might think, since so many other things change that affect performance in bigger ways.  Faster RAM, new sockets, and new support chipsets could become standard which may overwhelm the PCIe slot version advantage, so planning ahead only gets you so far.
I believe you have a point in futureproofing, next generation generation processors and ram might require new sockets and ram slots for which I will end up changing the motherboard again. So I there is no much point in getting a new motherboard for that purpose.

In terms of performance gain in games though, I think with PC Express 2.0 I will get 15 to 20% FPS boost in large texture games as suggested by the Benchmarks of Call Of Duty 4, Microsoft Flight Simulator and Crysis in the Toms Hardware review.
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Callandor
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Sorry for the delayed response my PC went down for couple of days

>>>Remember, it only occurs at very high quality settings for Crysis,<<<<

Come to think of it the all benchmarks were run at extreme resolution like1680 x 1050 and 1920 x 1200. I always run games at 1024 x 768 resolution at my 17 inch CRT monitor, so the  data transfer of the graphic card is less likely to saturate my PC Express 1.0, and my Geforce GTX260 is slower than the Geforce 9800GX2 in the review so that is another reduction in the likelyhood.


Yes, they have to use high resolutions in order to force differences to be evident between cards, because the cards are so powerful.  At normal resolutions, the benchmarks are too close.