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Odranoel1
03-16-2004, 11:35 AM
... are not yet available. Many of us are holding their breath for this technology.
Do we have any indication that AGP 8x is the bottleneck to be removed? I unfortunately have an outdated system, so I can only offer the idea:
Somebody would with a top end vid card could test the performance in FB with AGP at 8x and then at 4x. If there is a performance difference, then chances are that the new GPUs will benefit from PCI-E. If AGP 4x is fast enough for FB with current GPUs, then surely 8x should do for the next 2 generations, and we might as well not wait and do that long awaited upgrade as soon as ATI release their new card?

Odranoel1
03-16-2004, 11:35 AM
... are not yet available. Many of us are holding their breath for this technology.
Do we have any indication that AGP 8x is the bottleneck to be removed? I unfortunately have an outdated system, so I can only offer the idea:
Somebody would with a top end vid card could test the performance in FB with AGP at 8x and then at 4x. If there is a performance difference, then chances are that the new GPUs will benefit from PCI-E. If AGP 4x is fast enough for FB with current GPUs, then surely 8x should do for the next 2 generations, and we might as well not wait and do that long awaited upgrade as soon as ATI release their new card?

Cragger
03-16-2004, 11:46 AM
You wont seem much if any difference really. The PCI Express is more efficient in GPU to CPU transfers but even today's cards don't take full advantage of the bandwidth available on 8X AGP for texture data, which is becoming less and less important with more and more onboard vidoe memory.

Only the true diehards will see any gain for immediately switching out for a PCI Express motherboard and card and even then real gains will only come from 'tweaked' numbers I'm willing to bet.

The most critical components for IL2 are CPU, RAM, and then GPU. IL2 like many sims such as lockon are CPU intesive because of all the calculations constantly being performed and evaluated unlike FPS game where generally the hardest calculation is player tracking, collision detection and hit detection.

http://redspar.com/redrogue/cragger_sig.png

arcadeace
03-16-2004, 11:48 AM
Even from reputable hardware reviews the difference is usually not be much, assuming no bottlenecks with other components.

Keep in mind with the next generation GPU (ATI and NV) they should provide much more capability even without PCI Express.

clint-ruin
03-16-2004, 12:02 PM
Been a while since I've seen properly-done bandwidth testing, but last I looked, the main bottleneck with AGP is and never was the speed of throughput. It was that the card would lock the CPU out of accessing memory at the same time as AGP<->Memory operations.

As always we are probably only going to see modest performance gains from the new bus to start with - good for enabling faster speeds to be reached eventually, but probably not that great a boost for existing designs.

http://home.iprimus.com.au/djgwen/fb/leninkoba.jpg

Odranoel1
03-16-2004, 12:46 PM
http://ubbxforums.ubi.com/infopop/emoticons/icon_cool.gif Thank you all for the replies. It seems that everybody believe we will not see a major bus-driven performance boost with the first generations(s) of PCI-Express based GPUs.
I read elsewhere that the new (AGP-based) Radeon to be announced soon will have 12 pipelines (50% more than the 9800 family). That may well be all we need to run FB in 1600 x1200 with all whistles an bells?
MMh, been waiting almost 2 years now. I think I'll go for it...