Anybody know if Apple has plans to move away from PCI-X to PCI-Express? Or at least from AGP8xPro -> PCI-Express x16/20? I understand that PCI-X is optimal for XServe FC cards and networking, but it seems like the GPU industry is moving very quickly to PCI-Express for graphics

Only Apple knows. But I'd expect the next G5 rev to ship with PCI-E and some X800 GPU.

arekkusu Wrote:Only Apple knows. But I'd expect the next G5 rev to ship with PCI-E and some X800 GPU.

this is my same guessitimate too... their G5s have limitless room to put all kinds of new goodies in...

Otherwise Apple will run out of graphics options for the platform.

There will be AGP GPUs around for quite a while. A Radeon 9800 mobility will do the iBook just fine for the two years.

Well PCI-X and PCI-Express are geared toward different purposes, the same way we see PCI being used next to AGP. The difference is merely graphics have come to need more then what the existing PCI (and PCI-X for this next generation) slots can handle.

PCI-Express will be fun to play with...

As I understand it, PCI-E is serial/narrow/highfreq while PCI-X is parallel/wide/moderatefreq. And PCI-E has lane stacking for increased bandwidth. Also PCI-E not compatible with PCI 2.x like PCI-X.

As I see it, they do compete directly. Having 2 different PCI controllers seems like a waste when you can have 1 PCI-E controller doing both the graphics and add-on cards. I'm not exactly sure about the specifics, but it kinda seems like PCI-X is just trying to hold on to the past while PCI-E is moving forward.

I also like the idea of future systems with multiple slots with 16+ lanes (e.g. multiple fullband width graphics cards)

PCI-X is indeed somewhat legacy, but there is a lot of "legacy" hardware in the server world that will be in use for many more years, so PCI-X has its right of existence earned.

More importantly, though, PCI-X is a bus while PCIe uses point-to-point connections. It is very easy to add more slots to the PCI-X bus, for example with riser cards, but the same thing cannot be done for PCIe, which uses dedicated lanes to each slot. So, in an application where many cards with relatively humble bandwidth requirements need to communicate, PCI-X might have an advantage over PCIe.