Why is PCI Express being pushed so hard?

[DanDaMan315]

What exactly was wrong with AGP that we need a whole new infrastructure known as PCI Express? That is the question I am asking myself as I look at my "out of date" AGP slot. As far as I know AGP has years to go before the hardest core of gaming will ever reach its full potential. And other than SLI, which is kind of a waste, I see no point in the industry's move towards PCI-E. I hope someone comes in here and tells me I'm completely wrong because otherwise the computer industry is just pushing a new "faster" product that we don't even need yet.

On ATI's article about the x800XL and x850xt being released on AGP they basically said, we released it for those poor bastards that still have AGP. But if the the infrastructure isn't even close to being maxed, why is AGP being phased out so quickly.

Please help me understand what the need for PCI-E is.

 

[2thAche]

When AGP came out, people said the same thing. And the early cards, like Voodoo3, were basically just PCI cards on an AGP slot. Give things a couple years and you'll see the apps catch up with the tech.

 

[Vegito]

ur pci cards are all fighting for bandwidth, there isn't enuff for higher end scsi cards, raid adapters, etc.. imaging having something that offers nearly unlimited bandwidth.. well not unlimited but more than enough.. its like going from ISA to PCI, not we're going from PCI to PCI Express.. ISA -> PCI lasted like 10-15 years, from 86 -> 2000.. slowly isa disappear.. PCI -> PCIx - prob take another 4-5 year.. stuff gets cheaper and faster


Two PCIe devices are connected by a link, and each link is made up of one or more lanes. Each lane consists of two low-voltage, differential signal pairs carrying 2.5 Gbps of traffic in opposite directions. One pair is used for transmitting, and the other pair is used for receiving. To further increase the bandwidth of a link, multiple lanes can be placed in parallel (x1, x2, x4, x8, x12, x16, or x32 lanes) between two PCIe devices to aggregate the bandwidth of each individual lane. In the future, the signaling rate of the link can be increased to provide even more bandwidth.

 

[DanDaMan315]

But for the next few years PCI-E is unnecessary.

 

[n0cmonkey]

Originally posted by: DanDaMan315
But for the next few years PCI-E is unnecessary.

Yes, but if they push it now, they'll be able to utilize it sooner. You can't just let it sit there, develop some things that _will_ use it, and then expect everyone to have it. It'll take time before it's needed, which gives people time to get PCI Express systems.

 

[FishTankX]

What about ATA100? SATA? All unnecessary technologies, as hte harddrives we have right now aren't even close to maxing ATA 100, and probably can't max ATA66 under 90% of usage circumstances. Heck, in day to day use you could probably use them with ATA33 and still have it feel pretty responsive. Why did they push ATA100? Because they could.

 

[Bar81]

PCI-E is useful for some things that have needed more bandwidth for a while, just not graphics. It remains to be seen whether the next gen native PCI-E cards will feature radical design changes that necessitate the bandwidth PCI-E x16 can provide. I highly doubt it as the market is still AGP dominated and the next gen cards will need to have AGP variants. I would think 2006 is the first year we may see graphics cards needing the extra bandwidth of PCI-E.

 

[CQuinn]

1. PCI-Express is not just a replacement for AGP, it is a upgrade to the whole PCI concept.

We are already seeing and reaching the limits of PCI bus speeds. AGP was invented in the first place
to accomodate the greater bandwidth requirements of video over the rest of the system. So the
idea that we would eventually need to increase PCI performance for the rest of the system has always
been there.

2. AGP will be an 8 year old technology this year.

And it took a couple of those years before it was considered "mature" enough to replace PCI across the board.
If PCI-E spreads at the same rate, it will be 2007 (the 10 year mark for AGP) before PCI-E is widespread
enough to become the de facto standard. If the industry is not on a big push to start implementing PCI-E
now, then we could end up with the same situation as the "local bus wars" of the early 90's (with EISA, Microchannel,
VESA and PCI all competing to replace the aging ISA slot).

3. The limits for technology are already being pushed on the high end.

There are a few technologies that come close to pushing the limits for speed of the PCI bus.
SATA, Ultra320 SCSI (and soon SAS), Firewire 800, & Gigabit Ethernet for example. It has come to the point
where the bus itself can become a bottleneck for the rest of the system, especially on the high end of computer
server/workstation usage. It is more cost-effective to design PCI-E in for all systems, than to keep it at a
premium for only the systems that may push the technology today.

4. AGP does not allow to efficient two way data transfer.

AGP was originally designed to send massive amounts of data from the system to the video card, but not the other way around.

GPUs have become sophisticated enough that there is serious consideration of ways to offload some instructions from the
CPU to this other engine, for many types of mathmatically intensive uses. For this, AGP becomes a serious bottleneck, where
PCI-E was designed to take this need into account.

5. PCI-E is a solution for signalling issues with trying to create faster connection speeds.

PCI-E, as a serial connection with less wires used to facilitate data transfer, also can compensate better with the variances
between FSB, CPU, Memory and devices timing issues that often affect parallel PCI connections, and plague overclockers.

FishTankX, if I'm not mistaken, burst transfer rates and command signalling do meet or exceed the current ATA-100 spec.
The transfer of data is only part (an important part) of what information needs to be sent from the device to the rest
of the system. The idea of always keeping the signal speed higher than the data rate is to allow room for processing
overhead that is needed to support things like S.M.A.R.T, error-correction, NCQ/TCQ, RAID, and other useful features
of such devices.

 

[halfadder]

PCI-E is being pushed hard because it's new and better. The old AGP and PCI (even PCI-X) absolutely suck compared to PCI-E. If you want your PC to have any sort of decent I/O, you're going to want to use PCI-E anyway. Nobody is forcing you to buy new hardware, you could still buy a used 386 if you wanted to.

 

[fishmonger12]

Originally posted by: DanDaMan315
Are they trying to take our money?

always.

 

[imported_Computer MAn]

Originally posted by: fishmonger12

Originally posted by: DanDaMan315
Are they trying to take our money?

always.

lol but very true.

 

[akugami]

PCI-E is good for the bandwith reasons listed above. Even though the AGP 8x bus is not maxed out yet it's good to have something better and faster. Graphics aside, Ultra320 SCSI, gigabit ethernet and Firewire800 are pushing the limits of the PCI bus. It was simply time for something better. It might not have been needed this year or next but it was definitely needed. Pushing newere faster technology now will ensure that the transition is smooth and there is no huge performance gap due to the old technologies being heads and tails weaker in performance.

The ATA standards was pushed higher because it did help performance even if it wasn't by a whole lot. And it's quite different in the jump from AGP to PCI-E because ATA is backwards compatible. It's more like Firewire400 vs Firewire800 or AGP 1x vs AGP 8x. The AGP jump to PCI-E is probably more similar to PATA to SATA which was done for more bandwith (though not needed) and also because the SATA wires were smaller and less cumbersome (some stiffness aside) to route inside of a computer. It also didn't impeded airflow as much since the SATA cable is much smaller than a PATA cable.

 

[bunnyfubbles]

PCI-e is being pushed hard because lazy integrations are NOT good. IF they were not pushing PCI-e hard, companies would still be hanging onto AGP delaying the transition and preventing quicker advancements.

 

[sandorski]

Few opinions:

1) Bandwidth for Video cards will probably never be the issue. Video will just continue to get more onboard(oncard) memory until it exceeds regular system memory
2) PCI-e is a superior bus bandwidth wise, but the bandwidth will be more needed for other things such as HD controllers
3) smaller PCI-e sockets save real estate
4) most importantly for video cards and the most immediate benefit is that the PCI-e bus can supply higher voltages to video cards. This reduces the need to plug power directly into video cards.

 

[halfadder]

These days AGP sucks and plain old PCI sucks. They're ancient slow "technology".

PCI-E is what you need for any sort of real bandwidth. Why would you want anything less???

 

[Sqube]

Here's the way I look at it. New technology doesn't get used until there's an application for it. Applications aren't created until the technology is capable.

The tech people, in this case, decided to step up and get the ball rolling.

It's an "If you build it, they will come" type of thing.

 

[ribbon13]

Originally posted by: Sqube
It's an "If you build it, they will come" type of thing.

And they are
http://tyan.com/products/html/thunderk8we.html

 

[Ike0069]

Originally posted by: halfadder
These days AGP sucks and plain old PCI sucks. They're ancient slow "technology".

PCI-E is what you need for any sort of real bandwidth. Why would you want anything less???

I hope that was supposed to be a joke, because that's one of the most retarded statements I've read.

 

[Sqube]

Originally posted by: ribbon13

Originally posted by: Sqube
It's an "If you build it, they will come" type of thing.

And they are
http://tyan.com/products/html/thunderk8we.html

Sweet merciful sassafras!

 

[ribbon13]

AGP and PCI do indeed suck for anything requiring a lot of upstream bandwidth.

 

[halfadder]

Originally posted by: Ike0069

Originally posted by: halfadder
These days AGP sucks and plain old PCI sucks. They're ancient slow "technology".

PCI-E is what you need for any sort of real bandwidth. Why would you want anything less???

I hope that was supposed to be a joke, because that's one of the most retarded statements I've read.

There was a time when many thought EISA and VLB were plenty fast too...
It's time to move on to something with modern performance. AGP and plain PCI are waaaay past their "best if used by" date.

 

[Sqube]

A quote from that motherboard ribbon13 referenced:

Dual PCI Express x16 slots with FULL SPEED x16 lanes on each slot to support NVIDIA SLI? technology at unprecedented speeds

Doesn't SLI currently work by splitting the x16 lane into two x8 lanes? In which case, this board totally r0x0rs your s0x0rs to the extreme!!!!!!

 

[Ike0069]

Originally posted by: halfadder

Originally posted by: Ike0069

Originally posted by: halfadder
These days AGP sucks and plain old PCI sucks. They're ancient slow "technology".

PCI-E is what you need for any sort of real bandwidth. Why would you want anything less???

I hope that was supposed to be a joke, because that's one of the most retarded statements I've read.

There was a time when many thought EISA and VLB were plenty fast too...
It's time to move on to something with modern performance. AGP and plain PCI are waaaay past their "best if used by" date.

That's no the point. PCI-e is the future, but AGP is far from sucking right now. My AGP 6800 GT is just as fast as a PCI-e 6800 GT. So I'm not seeing your point here.

 

[Greenman]

It's a great way to sell a boat load of new hardware.

 

[halfadder]

Originally posted by: Ike0069

Originally posted by: halfadder

Originally posted by: Ike0069

Originally posted by: halfadder
These days AGP sucks and plain old PCI sucks. They're ancient slow "technology".

PCI-E is what you need for any sort of real bandwidth. Why would you want anything less???

I hope that was supposed to be a joke, because that's one of the most retarded statements I've read.

There was a time when many thought EISA and VLB were plenty fast too...
It's time to move on to something with modern performance. AGP and plain PCI are waaaay past their "best if used by" date.

That's no the point. PCI-e is the future, but AGP is far from sucking right now. My AGP 6800 GT is just as fast as a PCI-e 6800 GT. So I'm not seeing your point here.

Suction is relative. Now that we have PCI-E there is simply no need for AGP on a new or upgraded system. It's obsolete technology so why bother even wasting time discussing it? PCI-E is far faster and far better than even AGP 8x.

As they say: lead, follow, or get out of the way!