Future of PCI express

[imported_PanicAttack]

In the process of building a new PC and I can't seem to decide on which video card to pick and here's why.

Current video cards are all based on AGP designs and only transfer data one way at a time. I figure there will will be video cards coming out in the next year that can take advantage of PCIEs two-way bus that will greatly improve their performance. Yes/No?

Should I blow a wad on a current mid to high end card or buy a budget card and look to replace it when the new designs hit the market. Or am I looking at this all wrong?

Has anyone heard about the next generation of video cards? Will they even be PCI Express?

 

[harrkev]

I am not sure that this is the right forum, but here is my take.

At the very least you will not be at a disadvantage compared to AGP. And how will a two-way bus help? This is a video card! Data goes IN to the vid card. All data going out is to the monitor.

I admit that I am not a game programmer, but I would guess that if you added a two-way bus to a current card, the performance increase could be in the lower single-digit percentage points.

In short, if you want now, then buy now and be happy. No matter when you buy, there will always be something better just around the corner. If you are always waiting for the next big thig, then you will never buy, while all of your friends are happily fragging away on their 6-month-old vid cards.

In, in my opinion, any recent vid card can run any game that you care to name, but you might just have to turn AA off, which is not a big deal to me.

 

[imported_PanicAttack]

Thanks. Thought it might be a technical question is why I posted here. Your right about the IN/OUT I guess. But it's touted as the major advantage of PCI-E over AGP. Says each way is 4 Gigabytes for a total of 8 which sounds like a huge advantage which future video cards will be able to use.

 

[Rock Hydra]

There is more than data just going in. There is data being written to the memory and code sent to the CPU for processing. Parallel has an advantage when not a lot of data has to be sent at a time. Serial has the advantage of less EMI, also the same ammount of data can be sent on a faster bus using fewer bus lines and smaller traces. I'm sure if there was an AGP 16x, the interface between the card and the motherboard would be quite large. I'm thinking nearly a PCI-X or ISA sized slot. ;

 

[Sahakiel]

A lot of researchers got excited over PCI-E specifically because of the large bandwidth going back into the system. As far as I know, current video rendering does send data back, but not a whole lot relative to the data sent to the card. However, a lot of people want to see some non-rendering applications run on a video card and that requires bandwidth in the other direction.

 

[Calin]

If I remember correctly, the only "data-out" the video card send to the processor (well, the only data that would have an impact on the "video card to system" speed) would be the textures swapped from video card memory to system RAM (and back).

 

[realtrance]

The basic point of the vidcard being primarily an O device means PCI-Express will primarily be useful in the future if/when devs take advantage of the GPU as a second processor in the system for doing computational work beyond what is typical now for a video card.

PCI-Express enables this. Whether the current generation of video cards are capable of being exploited this way, though, is open to question (and answer here by someone more knowledgeable than me on the matter).

rt

 

[irwincur]

If I remember correctly, the only "data-out" the video card send to the processor (well, the only data that would have an impact on the "video card to system" speed) would be the textures swapped from video card memory to system RAM (and back).

This concept is even being put to use. Both nVidia and ATI will start to include less physical memory on their low end cards to take advantage of system memory. Does it work, yes, well, not really. Incidentally, this was also cited as a major benefit of AGP over PCI when it was released, that benefit promptly fizzled as it was tried and failed for the most part.

 

[ribbon13]

VIVO is one application where PCI-e will be a great boon. It should help immensely for cards that have built in video capture. Thus you can hook up your consoles to the vivo and play games on your pc monitor with much better picture and less lag than most of the video in on agp cards I've seen. And HDTV video capture. Signal in to capture and back out to real tv. I can think of many ways to use that bandwidth.

 

[highwire]

I really hope I'm wrong, but I think of PCI express as related to "change is progress".
If AGP X2 to AGP X4 has almost no effect and we already have AGP X8, What does "PCI whatever" give us except the oportunity to be "newer"

 

[Terumo]

Originally posted by: highwire
I really hope I'm wrong, but I think of PCI express as related to "change is progress".
If AGP X2 to AGP X4 has almost no effect and we already have AGP X8, What does "PCI whatever" give us except the oportunity to be "newer"

That's the question I ask too, as I sit here wondering which to go with on a budget.

In order to use PCI-E one would have to buy a motherboard and videocard at least to do so. But look at the pricing schemes of all of this -- the cheaper Nvidia 6600 cards are (correct me if I'm wrong it's the same with ATI) all PCI-E. Meanwhile someone wanting a decent AGP 8x card to upgrade their existing system has to pay much more. The manufacturers are almost pushing people to buy the PCI-E standard....but why?? Wouldn't it make sense to lower the AGP prices to sell out the old stock, and just make PCI-E? Apparently they're not doing that formula but really squeezing AGP users.

It's almost like the manufactuers have teamed up to force people to buy a whole new system to use a new technology -- and one so new that no one really knows if it'll be worth the switch.

 

[ribbon13]

It's easy to squeeze the gamer market, because it's comparitively small to the rest of thier business

 

[Peter]

You say it'd make sense to clear out AGP stock and solely make PCIE cards? And in the next sentence you complain about the manufacturers doing exactly that?

Coherency isn't your strong point. We knew that.

(Besides, AGP cards are still cheaper than PCIE throughout the range.)

PCIE as a technology on graphics cards overcomes many weak points of AGP - the fact that you can't have more than one AGP device, the slow upstream, the electrical fragility, the power restraints of non-pro slots. Besides that, it brings graphics chip interconnect back to a common technology with everything else.

As with any departing technology, the high end offers for AGP will fade fast because new chips and cards will be made to be PCIE, while midrange to low-end offerings will stay a while longer as the current (last) generation of AGP chips gradually slip down the performance pole and disappear. Those who have been in the industry long enough have seen exactly that happen with ISA and PCI graphics cards. Now it's AGP's time. In fact, this happens all the time in all areas. It's called progress. EDO-SDR-DDR-DDR2. CPU sockets. Power supply connectors. Case layouts. Display interfaces. Storage adapters. Even keyboard and mouse connectors.

For those who can't make up their minds, or desperately want to cling on to AGP for a while longer, there are chipsets and boards out there that let you have both AGP and PCIE.

But yes of course, if you like to have the benefits of the new architecture, you'll have to change to it. So? Buy a Ferrari and then whine you can't use up your Yugo tyres on it?

 

[Peter]

Originally posted by: PanicAttack
In the process of building a new PC and I can't seem to decide on which video card to pick and here's why.

Current video cards are all based on AGP designs and only transfer data one way at a time. I figure there will will be video cards coming out in the next year that can take advantage of PCIEs two-way bus that will greatly improve their performance. Yes/No?

As of today, there are graphics chips that are native PCIE. ATi's entire PCIE range, for example, all the way from budget X300SE to top notch X850XT. You don't HAVE to put up with an AGP chip with a bus bridge in front of it.

Regardless of what the future might bring, your best bet is to buy to your CURRENT needs, with a little headroom - and then look again when you've outgrown this.

 

[Terumo]

Originally posted by: Peter
You say it'd make sense to clear out AGP stock and solely make PCIE cards? And in the next sentence you complain about the manufacturers doing exactly that?

Coherency isn't your strong point. We knew that.

(Besides, AGP cards are still cheaper than PCIE throughout the range.)

Likewise, troll.

But you answered my question anyway (they're cheaper -- but the price tag doesn't reflect it -- which means what? More than supply and demand working to keep prices inflated ).

And to say that the gamer market is easier to squeeze isn't good enough. Because the gamer market is the advertising arm of the videocard industry. The gamer market is one that's willing to blow money away for bragging rights on things that only matter to gamers, not what matters to technology. They want to frag the fastest and, "how high can I OC this?". To the VC industry FPS, latency and OCing aren't the issue, what matters is profit. That's the whole bottom line: to get you the cheapest card to make at the highest profit ratio -- the bells and whistles are there to lure you in to buy their card.

Compounding the problem is the driver tweaking done to give artificial higher scores on benchmarks (what all that mainly matters to gamers -- bragging rights). The driver tweaking is a "soft" way to increase power with little upfront cost (cheaper to hire some programmers to tweak some code, than to retrofit an entire manufacturing plant). Meanwhile the hardware is about the same on every card, you'll be buying who wrote the better drivers than who has the best way to deliever the technology -- with a new hardware pathway to improve performance, for example.

It's not always what is the best hardware, as much as who does the most bragging, and for which VC maker based on driver tweaking that judges quality now.

And the other sad fact: the quest for higher speeds by the OCing community also increases the prices for everyone, as the VC industry has to factor the cost of all the RMAed cards due to pushing them. The VC makers don't care as they'll just pass the cost onto everyone else, their bottomline will always be met.

 

[Peter]

Going down to insult levels again? Not checking plain facts? Distracting from the original question? Throwing a ton of conspiracy blurb at a purely technical topic? We've had enough of that in your other favorite thread, thank you very much.

Baseline AGP cards are cheaper in retail shops than baseline PCIE cards - you need to check the real world facts. The original inquiry isn't about the top notch gamer market - you're distracting. Higher scores on anything (even if it's benchmarks) through software doesn't mean the hardware isn't improving - you're making up your own myths again, including false conclusions that look good through rhetorics. The OC community inflating prices for everyone - here's your conspiracy of the day. Answers to the original question - null. As usual.

I'm infinitely bored with you.

 

[Terumo]

You're reaching for reaching sake, Peter.

Try searching pricewatch for a baseline PCI-E and a good AGP card. You'll find the prices for the PCI-E cards are cheaper than AGP.

Let's give you a crash course of numbers (lowest prices on Pricewatch)....

Geforce PCX 5900 128MB = $159
Geforce FX 5900 128MB = $173

Geforce FX 5600 Ultra 128MB = $199
Geforce 6600 128MB = $128

These are comparible models but the PCI-E is cheaper. If someone wants to buy a new 2 year-old technology wise videocard, yeah Peter you are right the AGP is cheaper. But if you want a card that can make the most use of an AGP only motherboard, you're going to pay royally (if you can find it).

 

[Jack31081]

Originally posted by: Peter
You say it'd make sense to clear out AGP stock and solely make PCIE cards? And in the next sentence you complain about the manufacturers doing exactly that?

Coherency isn't your strong point. We knew that.

(Besides, AGP cards are still cheaper than PCIE throughout the range.)

Funny...I seemed to understand her just fine.

And no, AGP cards are NOT cheaper throughout the range. I bought my PCI-E 6600GT for $180 and change. The cheapest AGP 6600GT was around $220.

The gap has closed a bit, but at newegg, the cheapest PCI-E 6600GT is $184 and the cheapest AGP 6600GT is $205.

 

[ribbon13]

If moore's law holds true for GPU's than I think PCIe is good. 16x should ge good enough for at least 6 years

 

[Peter]

I said BASELINE for a reason.

The entry point for DX9 hardware from ATi (who make _native_ AGP and PCIE chips across the board, to avoid added cost for either type of card - I said that) is around $60 for AGP and $85 for PCIE. (Retail pack, Newegg prices as of today).

Midrange, just for the fun of it: 9600XT AGP $130, X600XT PCIE $145. (128-MByte retail packs).

6600GT? Two facts: The AGP version is fresh in, prices inflated by high initial demand - and by the use of a rather expensive bridge chip. There is no native AGP version of the 6600 chip itself. It's a PCIE design with a converter slapped on. Extra chip, extra PCB space, extra heatsink. Not free. And of course, thanks to the extra bridge hop, performance is further down than the constraints of AGP would mandate.

The top end, as small a market share as it is, has already shifted to PCIE. X800XT is already cheaper in PCIE than AGP, by about $20 in a $500 card. That's not much, and not a surprise either - using old AGP infrastructure isn't going to get you today's top notch performance regardless of how much money you spend. This is the one range where PCIE sales have outgrown AGP sales already. Still, prices aren't differing enough to make reasonable people whine - 4 percent, no point here, move on please.
Meanwhile, the prices for the best AGP cards aren't going down just because the platform is on its way out. Market forces basics - supply is drying up faster than the demand. No manufacturer would lower their prices for a stock clearance when people are queuing round the block anyway.

Let's not forget the original poster's concern: The question was, why pay extra for PCIE when the chips are all AGP-with-bridge anyway? My answer, again: There are native PCIE chips NOW, and they actually do perform better than AGP chips ever could (e.g. in things like HDTV decoding). My extra advice: Don't pay the (ridiculous) price premiums for a top notch card if you don't need one. Go PCIE, buy reasonably, upgrade later as needed.

Terumo, that answers your question too: "Decent" AGP can be had for less than same-performance PCIE. If you want top notch performance AND stay with AGP nonetheless, that's a contradiction in itself. Technology has moved on.

 

[uOpt]

Anybody has real data how fast you can read back a frame out of a PCIe card compared to a similar AGP card?

There are a number of purposes for this:

- high-speed rendering of 3D images, e.g. for web applications

- render something into the card which you read back out, then feed it back in, e.g. to use as a texture, or to do level-of-detail, or to do unsharpening to areas of the frame you want out-of-focus

I would be curious whether PCIe offers a serious advantage at this time. It should, but I haven't seen numbers.

 

[Peter]

Readback out of video memory (by means of the CPU) is still going to stink. What you want to do is make the GPU push the frame back into system RAM. That's exactly where AGP couldn't transfer faster than 66 MHz, blocking out traffic heading the other way as well. PCIE lets you transfer from GPU into the system at the same high speed as the other way round, and the bus is fullduplex with independent transmit and receive lanes.

 

[Matthias99]

Originally posted by: MartinCracauer
Anybody has real data how fast you can read back a frame out of a PCIe card compared to a similar AGP card?

I don't have a firm number on this, but I think PCIe has a lower latency. It definitely has a MUCH higher bandwidth (although this would only really come into play with things like HD video encoding, etc.) For something like just getting a framegrab, I doubt it would be a huge difference.

- render something into the card which you read back out, then feed it back in, e.g. to use as a texture, or to do level-of-detail, or to do unsharpening to areas of the frame you want out-of-focus

If you implement things like this through shader programs, you don't need to transfer the data out of the card at all. That's how most real-time motion-blur/depth-of-field effects work, and I know you can render output from a pixel shader to a texture (which can then be used for input to another shader, or just used like a regular texture). There's usually no need to bring the data back to the CPU if all you're going to do is to feed it into another shader or render it on the screen.

 

[imported_aten]

the apple g5 comes with PCI-X is that PCI or PCI express?
thanks
www.twesh.tk

 

[kpb]

PCI - x is 64bit 133 mhz version of the old 32bit 33mhz pci slots not pci express. Obviously being twice as wide and 4 times faster makes it much faster but they are still slower than pci express slots and much more expensive.