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AGP4X vs. AGP8X
An anonymous reader writes "With upcoming chipsets such as the SiS648 claiming support for the latest AGP8X standard, we asked ourselves if there were any performance benefits. We took the SiS648 and Xabre 400 reference boards, modified them and compared the results." I can't even get 4x stable under XP, so I figure 8x is
half as likely to let me play NWN :)
you building your own motherboards or something? What mainstream motherboard doesn't have AGP 4x?
2.18 gigabytes a second. Jesus - does anyone else see why this is wierd to me? I mean, I understand the need for faster hardware, but can't software producers just make their software more efficient? I mean, any game I'm playing that requires 2.18gb of data to be passed through my video card each second is going to require a better, faster computer than I've got now. I'm tired of always being forced into upgrading just to play the latest and greatest games - and then being told that I'm breaking the law when I want to play old ones that I can't buy anymore! It's absurd, and it makes perfect sense - too many software companies have a vested interest in hardware - the more advanced the game, the more hardware that sells. What we really need is another Mario Bros. or Tetris to come along to give us all a kick in the face - great games don't need outstanding graphics to be great fun.
dammit i was trying to post some replies on the forums when suddenly the server stopped responding
thanks for slashdotting the server. thanks a lot.
i was wondering why the sudden slowdown when its 4am here (singapore), and i launch a new browser window, and the first thing i see is the agp 4x vs 8x article, and the page linked is hardwarezone.
Basically, SiS has come out of nowhere with motherboards that absolutely trash the competition in regards to performance and features. It started last year with the SiS 735, the best performing Athlon mobo of the year. Sadly, it was a poor overclocker, so it was shunned by AMD fans. But this year SiS has had a string of hits. It's the only 3rd party with a P4 license, which makes it the only choice for mobo manufactures in terms of 3rd party P4 mobos (obviosuly they're ansty about Intel frowning upon their Via-based P4 boards, seeing as Via doesn't have a valid P4 license). The SiS 645, 645DX, and now the 648 have consistently been of high quality with features no one else has. The 645 introduced MuTIOL which doubled the bandwidth between north and south bridges, to 533MB/s. The 645DX introduced unnofficial, rock solid DDR400 support. Now the 648 again doubles bandwidth between north and south bridges to 1 GB/s, it introduces AGP 8x, and it probably will officially support DDR400. SiS 648 boards also have Serial ATA support. This is a far cry from a decade ago, when everyone knew SiS=shit.
This review / test is bullshit. The only reason that they see an improvement in lower resolutions is that its the only resolution where the game / app is not limited by the video card.
/. editors will stop "jumping the gun" and wait until some real reviews come out. This is like testing a new high performance tires that can go upto 400/mph with a Yugo. Is anyone going to be surprised when the $25 tire performs just as good as a $400 tire? Sorry for the lame analogy, haven't had my morning Coke. :-p
I'd definitely take this with a grain of salt until someone can do a 4x/8x review with a NV30 or a ATI 9700.
What kind of hardware guy looks at this and doesnt say "WTF Xabre 4000?? What kind of video card is that to benchmark anything?"
Hopefully the
-- D3X
Most people will say agp8x is way too much and overkill and will introduce some bugs and firmware/hardware/signal issues with some lower quality cards, etc...
:)
Well, when AGP 1x was out, people didn't find it very useful because it wasn't fast enough
AGP2x was okay to offload the PCI bus and do some basic stuff, but not fast enough for high-speed games and transfering large chunks of information.
AGP4x seems to be okay for today's technology and all, and AGP8X seems to be way overkill, but I personnaly think that it's finally what it should have been since the start: a *VERY* fast graphics port on which the bandwidth bottlenect doesn't become an issue, * at any resolutions * , and that help cutting down the cost in other fields beside gaming. (one example: uncompressed video editing 1600x1200@24bits(or more for film and with newer card with better colorspace) @60FPS) Right now you require exotic hardware for this, especially for uncompressed playback. let's say you'd want to invest on a fast Ultra320 array (ok you'll say if you do so you can afford the exotic hardware as well, but the point here is actually CUTTING down the price, and this is one way), well now you could get way more drives for your system.
There are many more examples for this, but the main idea is there are new features that are going to come out for cards, bigger bitdepth, better this and that, that's going to choke the bandwidth and 256MB on a card won't be enough in a not so distant future, using system memory at almost local memory speed increases quality and possibilities tremendously, and while we don't see much use right now, I'm sure it won't take long after 8x is installed that we'll see a use for 12x or 16x
--- Metamoderating abusive downgraders since my 300th post.
"Don't hold your breath waiting for it. When we announced it we didn't realize that Linux owners are all cheap fucks who don't pay for games."
I have a ATI AIW 32MB DDR, and my tribes2 can get a lil laggy esp when their are some vehicles on my screen.
reading my X log I notices that DRI was using 1X mode for AGP. after some RTFM, I found the option to kick it into 4x.
Anyway the point being it didn't help speed up the game gfx (well i didn't notice much difference)
In case ur wondering for ATI cards the XF86Config option is:
Option "AGPMode" "4"
Also i noticed:
Option "AGPSize" "32"
But i cant tell if setting this bigger then the ram on the card helps or not (maybe that the buffer size opt?), was hoping to let the card borrow more of my sys ram (which is pc100, slow compared to gfx cards DDR, but better then hdd =)
anyone know any other good opts to help eek more speed?
"[...]there's actually quite a bit of advantage with AGP8X especially at lower resolutions."
What are these people smoking? The vast majority of the tests are all but identical. The VERY BEST performance difference is 3DMark2001SE Pro at 800x600x16, and it shows a whopping 4.7% improvement.
Clue: In the current 3D world, AGP4X IS NOT a constraint. Even AGP2X is fine. Hell, there was an early version of the (TNT2 or GeForce 1, I forget which) that was *PCI*, for chrissake, and it was only a whisker slower than the AGP cards at the time.
Geometry transfer, it would appear, just isn't very bandwidth intensive. The only time the AGP rate is going to matter much is when doing very heavy texturing from main memory, but that just isn't happening. Instead, manufacturers are putting more and more RAM on the video card instead, and all the games are oriented around pre-loading all necessary textures in that specialized, super-high-speed RAM.
At the present 1.06 MB/sec transfer rate of AGP 4X, that means that the entire video RAM of a 128MB card be filled in roughly 1/10th of a second. If you spend all the time, money, and effort to upgrade to AGP 8X, you can improve your load time by 1/20th of a second.
Just think...if you played 50 levels of some FPS a day, every day, you'd save over 15 minutes in your first year alone!
Obviously, this is a very important technology we should all rush out to buy. Thanks, hardwarezone.com! I'll trust you for all my technology reviews in future.
-----
AGP8X: Saving your time so efficiently, you won't even notice.
Well, when AGP 1x was out, people didn't find it very useful because it wasn't fast enough
AGP2x was okay to offload the PCI bus and do some basic stuff, but not fast enough for high-speed games and transfering large chunks of information.
Not fast enough to be useful? What reviews were you reading?
Back when AGP 1x and 2x were rolled out, they were found to be marginally useful because the graphics card was the bottleneck. This is true even today. Fill rate is still almost invariably the bottleneck for performance, and CPU power for geometry and physics is usually second.
The original intent of AGP was to transfer textures across the bus, with the card's texture memory just a cache of this data. But this is a _bad_ thing to do - bandwidth and especially latency of a card's on-board memory is likely to be much better than AGP transfer bandwidth and latency, so nobody in their right mind writes games that require streaming textures from system memory. This isn't going to change - the memory in your PC is optimized for being big. The memory in your graphics card is optimized for being fast. Even with a zero-latency, infinite-bandwidth AGP port, local memory is better.
All AGP is used for now is to transfer geometry data, and it's plenty fast for that (cards are still generally fill-rate limited). With on-board transformation and lighting, and further folding-in of the graphics pipeline on the way, the amount of data that needs to be transferred per frame is going to get _smaller_, not larger.
Very high AGP transfer rates are a marketing bullet-point, and not much else.
Oh, and if you're editing a 1600x1200 movie on a PC, you're limited by your disk transfer rate. No way are you storing *any* significant chunk of that in a PC's RAM.
It seems like the editors have a particular list of text strings they grep all incoming submissions for, apparently among these is AGP8x. This comparison is ridiculous even for Rob to point heedlessly to. The wbesite itself is Yet Another Anandtech/Tom's Hardware ripoff design with an article that reads like a SiS fanboy on crack.
The whining and crying about AGP 8x is a bit premature and the AGP 3.0 standard has been pretty much supplanted in usefulness by graphics card manufacturers. Having a dedicated high speed port for graphics hooked up to the northbridge is a good design idea. It frees the traditionally low bandwidth nb-sb connection from needing to carry lots of graphics data. The memory sharing available in AGP has become increasingly useless as worthwhile graphics cards have scads of local memory now. About the only thing an AGP apeture is good for is an i845G chipset board or some other cheap piece of shit HPaq sticks in their computers.
The AGP 2.0 spec isn't much of a bottleneck either. Case in point, replacing the TNT2 based video card in my dual P3 500 with a GF2GTS more than doubled the 3DMark2001 SE score from 926 to 2068. The board is an IWill DBD-100 with a 2x AGP port on it. The fillrate or poly rendering ability was not adversely affected by the AGP 2x port, the only thing keeping the 3DMark score down is the relatively slow processors (as 3DMark is single threaded) and the low FSB bandwidth.
The fillrate of an ATi R300 or nVidia NV30 isn't going to affected much by an AGP bandwidth on ONLY 1GB/s. Most cards based on these chips will end up having >100MB of on board memory. It won't be too terribly long before the video card in the PC has more and faster memory than the system's main memory. Even Doom3's 80MB of textures isn't going to really stress a 4x AGP card, it would take all of a seventh of a second to transfer all 80MB of textures. Maybe AGP 8x will be on my upgrade path when the load time of a game's textures take a perceptible amount of time to load into the video card's local memory.
Rob it isn't Microsoft's fucking fault your AGP card doesn't work properly, you're probably stuck with some old VA Lin^H^H^HSoftware POS box. My system doesn't have any problems running reliably under Windows XP and I don't think too many other people running Windows 2000 or XP are having too many problems either. When do we get to mod the editors as -1 Troll?
I'm a loner Dottie, a Rebel.
Well, 4.7% max increase. On one single benchmark at a low resolution and the rest of the benchmarks showed between close to no performance improvement to worse performance. I wonder who paid that reviewer to be even close to lukewarm because he sure as hell had no data to say anything but 'total junk with this generation gfx cards, dont spend a dime on it unless you plan on buying a $1k graphics card in the near future because by the time it'll make a difference at consumer gfx card levels it's gonna be time for a new motherboard anyway'.
Since the only noted difference is at lower resolutions it means the gfx core is the slowdown at any higher resolution which means the gfx core has to get a lot faster before the AGP bandwidth becomes the actual bottleneck. Which means one or two gfx core generations until you'll need faster AGP.
So, dont worry, there'll be no requirement for AGP 8x for any game that wants to sell more than a dozen copies in the next three years at least.
SiS has been doing motherboard chipsets since at least the 486 era, and I/O cards before that. I've also had SiS-based motherboards, and they had bugs and instabilities I'd never even heard of before. I've long since come to associate SiS chipsets with the mobo mfgr cutting corners, and haven't seen anything yet to make me change my mind. (Tho the SiS-based I/O cards for 386/486 machines seemed to be pretty good in their day.)
... gee, I wonder if that's why SiS chipsets need heatsinks, even when no other chipset in the same class needs 'em.
As to another poster who says he likes SiS because of the "low heat/low power"
~REZ~ #43301. Who'd fake being me anyway?
This tomshardware article from a while back compares AGP 1x -> 4x... here were the results. You can see that even in the beginning of 2000, the benefits of higher AGP speed showed diminishing marginal returns.
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