AGP v. PCI Express - Question

[sbrylski06]

Basically, which one is better?

I have two conflicting reports:

- One says that video cards are shifting towards using the PCI Express slot, and will soon be only manufactured for it.

- One says that AGP is still the best and most common video card slot.

That got me confused. Putting the two reports together myself, I concluded this:

AGP is currently more common and runs just as fast as PCI Express, but the industry is shifting toward PCI Express because it has the potential to go faster. The current difference between AGP and PCI Express is minimal, but in the near future cards will come out configured for the PCI Express that will run much faster than AGP will ever run.

Is this correct?

I'm buying a new motherboard and would like to know for sure if I want the AGP slot(s) on there.

I also know about SLI, but I feel that I don't game enough to want to spend that kind of money on two video cards. And my case only supports microATX...

 

[Akhenaton]

Is this correct?

Yes, it IS correct. It can be shown with theoretical BW calculations, that PCIe doesn't offer any real life attainable performance advantage over good AGP 8x chipsets. It was around 2004 when serious HW sites did benchmarks and proved that even 4x was enough up to about 8 Gtexel/s fillrate.

Another way to put it is that if you have an old machine with AGP graphics, there is still (contrary to industry pundits) no need to upgrade your motherboard, just get a midline -1 generation graphics card with AGP support (these come pretty cheap these days when inventories are being purged). When you upgrade next time within say 2008, you will get a new MB and PCIe graphics.

Only if you are looking for a high end solution, then you must go for PCIe (meaning 7800 series or X1800/1900), because the serial protocol and SLI/CrossFire support will give you that extra few percentage which might in theory make a difference at high resolution frame buffer/FSAA high BW demand transfers.

However, if you have already decided to upgrade your core system (including MB), then a sensible choice is to migrate to PCIe graphics at this point for future proofing. Unless ofcourse, you plan your MB to be a transition solution for only one year of use/only midrange graphics requirements for the next 2+ years.

These are ofcourse all personal opinions, based on over 15 years of system building.

 

[Zanmato]

In full agreement with Akhenaton, at the moment there is no real performance gain from switching to PCIe. Most cards are technically the same. If you are going to get a new system motherboard, then get one with a PCIe slot now as AGP will soon be phased out. If you get one with AGP you might be stuck with it and whatever you have in the AGP slot. I also was told the same when I was upgrading to get a new system (shop attempting to shove a new system in my face) but I would rather wait and get a better system with PCIe than getting a new system now for the same money 12 months down the line. It was cheaper for me just to upgrade the card for now.