Slashdot Mirror
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 :)
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.
The really weird part is that a few grams of wet meat at the back of your eye can actually process and perceive 2.18 gigabytes per second of information.
Then within a few milliseconds, more meat analyzes it, distills it into high-level representations, calculates 3-D trajectories, then moves meat-based servos to aim and fire weapons. All for no other reason than it seems fun.
Life is strange.
"[...]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.