what will be the next local bus to replace PCI?

[wviperw]

PCI is starting to not be able to keep up w/ the processor. It still is only running at a measily pace of 33mhz isn't it? If you set it to go higher you might strain the cards. So what will come next? Not only is there a need for more speed but also for more width. 64bit possibly? Running at the clock of the CPU? Perhaps modifying the existing AGP 4x architecture to accomodate more than just video cards.

What about a separate processor dedicated to the bus. That way it doesn't need to go through the PCI Bus IO Controller. This would also take some of the load of the main processor.

Sooner or later we will need to replace this aging bus. Any ideas? Are there any companies currently working on it? In the past Intel and IBM have usually introduced new architectures.

 

[Noriaki]

AGP is a Port, not a Bus. It's an adapted PCI spec, but because it's a port it can only handle a single device.

PCI-X is likely the next bus spec for PCs.

It's very flexible in it's configuration, and is backwards compatible with current PCI.
I think you can get up to 533MB/s out of PCI-X depending on the configuration.

 

[wviperw]

AGP could be adapted to a bus though can't it? Although it wouldn't be a very good idea when you could just use PCIX like you were saying. AGP2X transfers 528mb I think. So AGP4X would transfer 1056mb (I seem to remember it being able to translate 1.5gb or something like that)

 

[SCSIRAID]

PCI-X is the next generation. 133Mhz 64 bit yields 1 GB/sec rates. Futures may 'double pump' PCI-X for even faster speeds. Beyond that could be Infiniband however it is more suitable for CPU-CPU interconections rather than simple peripherals.

 

[jonnyGURU]

<< AGP could be adapted to a bus though can't it? >>

As Noriaki stated: No. AGP couldn't be adapted to a bus. It's speed is a modification of the existing PCI bus standard (multiple cycles on the PCI 33 MHz bus). To make the bus speed as much as the AGP slot can accept, it wouldn't be AGP or PCI... it would be something else altogether.

I'm with SCSIRAID on the PCI-X... although I have to admit that currently my system has PCI-64 and I STILL don't know what to put in these slots (suggestions welcome ).

 

[RedBeard0531]

This may be way out in left field, but what about a super-highspeed serial bus, like sata. Each device could set its own speed and cruise instead of PCI = 1/4 fsb. IMHO that would alow realy high fsb overclocking.

 

[wolf550e]

I know its a bit off topic, but what are those new typ of slots which look like pci but backwards, i.e. short part closer to edge?

 

[jaydee]

<< I know its a bit off topic, but what are those new typ of slots which look like pci but backwards, i.e. short part closer to edge? >>


You mean CNR slots?

 

[RedBeard0531]

<< You mean CNR slots? >>


No, the slot he is talking about is via specific, but it is similer to amr/cnr

 

[Pyro]

Yeah, PCI-X is slated to be the next big thing, but what about AMD's HyperTransport? Couldn't that be adapted to replace PCI?

 

[Noriaki]

HyperTransport is a bus to connect the North Bridge to South Bridge I believe, it's not going to replace PCI's functionality.

Current chipsets use the PCI bus for that function, but most new ones are not. They PCI function is solely in the south bridge on new chipsets.

It's like Intel's Hub archtecture, or Via's V-Link.



<< This may be way out in left field, but what about a super-highspeed serial bus, like sata. >>

Actually current Parallel ATA is slower than PCI. Much less PCI64/66. I believe Serial ATA is only about 2x as fast as Parallel ATA in it's first form.

Still under half of PCI64/66.

Serial ATA is quite fast when compared to hard drives, but you have to realize hard drives are several orders of magnitude slower than anything non-mechanical.

SATA isn't near as fast as PCI-X.

 

[RedBeard0531]

I was merly using that as an exapmle. Basicly reducing the bitwidth but increasing the frequency.

 

[Pyro]

I thought HyperTransport was a general spec, not for south to north chip only.

I heard some companies will start using it for their switches, where they need tons of speed.

I see no reason why HT could't be applied to function as a PCI type bus.

 

[MrHelpful]

IIRC, PCI-X's bandwidth is split between all of the present PCI cards, so if five cards were present, the bandwidth would be split into 5 parts? The bandwidth then wouldn't be all that much to talk about, right?

Something must be wrong with the way I am thinking...

 

[RedBeard0531]

<< The bandwidth then wouldn't be all that much to talk about, right? >>


That is only true when all devices are using all their bandwidth.


<< Something must be wrong with the way I am thinking... >>

 

[PC Freak]

Forget copper and other wiring. Everything in a computer should go to fiber and other uses of light. my 0.02cents

 

[ERJ]

I agree that an optical bus would be pretty cool but wouldn't the mechanisms for translating to and from the optical signal for the peripherals and CPU negate any real advantage to this? I guess that we will have to develop full optical CPUs then

ERJ

 

[RedBeard0531]

I thought that the only benifets of optical are increased security(not important), increased max legnth(not important), and zero noise. While the noise issue might be important, I think that the current settup is just fine.

 

[dmk11]

I think Intel is trying to push Infiniband to replace PCI.
There's also RapidIO - not sure if this is something that can replace PCI, but it's another standard that's trying to get some airtime out there.

 

[HansXP]

<< I know its a bit off topic, but what are those new typ of slots which look like pci but backwards, i.e. short part closer to edge? >>



Those are ACR slots. Basically next gen AMR, with full backwards compatibility. No, I don't think anyone will use ACR either...

 

[bil]

Does anyone know when these newer interfaces will start to be phased in to mobos?

 

[SCSIRAID]

PCI-X is rollong out now in the server space. The mainstream space is way behind with only 32 bit 33Mhz PCI. I would expect to see 64 bit or 66 Mhz before PCI-X.

The first release of Infiniband actually has less bandwidth that PCI-X 133 Mhz 64 bit.