PCI-X versus PCI - any benefit for me?

[CoffeeMonkey]

I'm probably worrying way too much about this, but here goes:

If I get a new G5 with three PCI-X slots, and a couple of years down the road PCI-Express becomes the standard, is my choice of video cards going to become more limited than they already are as a Mac user?

Is there any chance that new video cards would be backward-compatible with PCI but NOT PCI-X? I keep reading about how PCI-X is going the way of the dodo. Even if PCI becomes obsolete, it will at least be an extremely common obsolete technology, so I could probably expect some legacy support.

If there is any risk, is there any offsetting benefit for using PCI-X for a casual user?

Thanks in advance for any advice you can provide!

 

[Veldek]

I'm probably worrying way too much about this, but here goes:

If I get a new G5 with three PCI-X slots, and a couple of years down the road PCI-Express becomes the standard, is my choice of video cards going to become more limited than they already are as a Mac user?

Is there any chance that new video cards would be backward-compatible with PCI but NOT PCI-X? I keep reading about how PCI-X is going the way of the dodo. Even if PCI becomes obsolete, it will at least be an extremely common obsolete technology, so I could probably expect some legacy support.

If there is any risk, is there any offsetting benefit for using PCI-X for a casual user?

Thanks in advance for any advice you can provide!

Your choice of graphics cards won't be limited as the Power Mac uses AGP for these cards and NOT PCI-X. But there could be PCI-Extreme 1x which is the successor of PCI and could also make PCI-X obsolete. But as PCI-X is backwards compatible to at least some PCI cards (3.3V), your choice won't be too bad there, too.

 

[Trekkie]

Your choice of graphics cards won't be limited as the Power Mac uses AGP for these cards and NOT PCI-X. But there could be PCI-Extreme 1x which is the successor of PCI and could also make PCI-X obsolete. But as PCI-X is backwards compatible to at least some PCI cards (3.3V), your choice won't be too bad there, too.

Bzzt. Uh, no.

AGP is going away. PCI-e 16x is replacing it. There are systems & graphics adapters already releasing/about to release in the Intel world with these features.

However since Intel is the driving force behind PCI-e migration AMD systems (and hypertransport) don't appear to be moving as quickly to PCI-e. So it may be that AMD and Apple use AGP while Intel uses PCI-e for the latter half of 2004 and maybe first part of 2005.

I'm always hoping for a PCI-e 16x slot in the 3.0GHz DP G5 though. That and no more ADC would make things easier. I'd probably always buy an apple monitor but I'd like the option not too.

 

[Veldek]

Bzzt. Uh, no.

AGP is going away. PCI-e 16x is replacing it. There are systems & graphics adapters already releasing/about to release in the Intel world with these features.

However since Intel is the driving force behind PCI-e migration AMD systems (and hypertransport) don't appear to be moving as quickly to PCI-e. So it may be that AMD and Apple use AGP while Intel uses PCI-e for the latter half of 2004 and maybe first part of 2005.

I'm always hoping for a PCI-e 16x slot in the 3.0GHz DP G5 though. That and no more ADC would make things easier. I'd probably always buy an apple monitor but I'd like the option not too.

You have to pay attention. Of course, you are right, but he didn't ask about AGP, but wanted to know about PCI-X.

 

[jsw]

I guess the literal truth is that, yes, you'll be at a disadvantage if PCI Express takes off as the video card standard and AGP is shelved.

The practical truth, though, is that your new G5 won't be the only new/almost new computer out there without PCI Express. Not a lot of the PCs have it yet, and certainly there are millions of very new PCs without it.

Therefore, it'll be quite some time before AGP is outdated. Manufacturers will continue to make new AGP cards. Some tiny percent will get ported to the Mac, as always. Hence, the AGP slot on the G5 will work with nice video cards for some time to come.

The question of whether PCI Express will be needed for other things is one I can't answer. My understanding is that people are primarily concerned that it'll prohibit them from using new video cards. By the time you'll 'need' a PCI Express card, you'll 'need' a new Mac anyway....

 

[Trekkie]

You have to pay attention. Of course, you are right, but he didn't ask about AGP, but wanted to know about PCI-X.

I *did* pay attention, you didn't.

AGP is going away just like PCI-X in favor of PCI-e. It affects both. So because the video is AGP and not PCI-X doesn't mean that he/she is safe, it means that you need to be concerned about that as well.

 

[Trekkie]

I guess the literal truth is that, yes, you'll be at a disadvantage if PCI Express takes off as the video card standard and AGP is shelved.

You're new around here aren't you?

Intel is driving the migration to PCI-e. The pressure from them to drop AGP will be immense and I'd be willing to bet money the 'top end' video cards will only show up as PCI-e....

 

[Veldek]

I *did* pay attention, you didn't.

AGP is going away just like PCI-X in favor of PCI-e. It affects both. So because the video is AGP and not PCI-X doesn't mean that he/she is safe, it means that you need to be concerned about that as well.

I said you were right, but let me quote the original question:

"If I get a new G5 with three PCI-X slots, and a couple of years down the road PCI-Express becomes the standard, is my choice of video cards going to become more limited than they already are as a Mac user?"

So, if he has PCI-X and PCI-Express becomes standard, then this has NOTHING to do with his choice of graphics cards. So, clearly, it was you who didn't pay attention. Again: you are right, as soon as PCI-Extreme replaces AGP, his choice will become more and more limited, but that hasn't been the question here.

 

[CoffeeMonkey]

maybe I asked the wrong question

Thanks for all the input. I've realized that I'm less concerned with how long before PCI-Express becomes the "standard" than I am with how long I can count on PCI-X support.

I've only been a Mac user for three years now, so I don't know how they've handled things in the past, so can anyone tell me how long you think I can count on Apple supporting PCI-X? Isn't that a pretty new technology as far as Mac desktops go?

 

[Mac Maven]

I'm suffering over the same predicament as you are, CoffeeMonkey. I currently have a DP2.0/9800XT on order at the Apple Store, scheduled to ship on the 7th or 9th of next month. I've been torturing myself and my family over this decision. We need a new desktop, but we also need it to last for many years to come. It seems like everyone's getting on board with PCI-e, so the obsolescence pressure on machines without it will be substantial. I don't want to make a significant expenditure with this looming on the horizon. So I'm leaning toward canceling my order. One cannot be at all sure when Apple will implement PCI-e, but one may infer from past performance that it's going to take awhile. Take a look at how long it took Apple to introduce DDR, for instance.

As far as PCI-X support is concerned, you shouldn't be fearful. At worse, you'll buy PCI-X cards that you won't be able to take with you to your next machine, which may feature PCI-e only. But from what I've read, PC motherboard manufacturers are showing off boards with PCI-e and PCI-X. It makes sense to maintain PCI-X for backward compatibility purposes. I wish us all luck with our purchasing decisions.