Catalyst 4.12 likes extreme AGP Aperture on 256mb card

Ripsaw

I've been experimenting trying to clear up some graphic stuttering issues with Catalyst 4.12 on my Sapphire 9600XT 256mb card. Actually the only game affected was Call of Duty United Offensive, which runs in OpenGL. But it annoyed me nonetheless, since CoD is my fave way to waste time.

4.12 w/ Catalyst Control Center (and the underlying .NET Framework) caused moderate stuttering, and 4.12 w/ classic ATI Control Panel eliminated most of the problem, although some minor stuttering remained. On a scale of 1 - 10, stuttering under 4.12 w/ CCC was about a 7, under 4.12 w/ classic control panel it was about a 3.

Above was using BIOS default AGP Aperture of 64M.

So lastnight I tried 128M Aperture. No difference. Then 256M, no better.

Dropped Aperture to 32M, which is as low as my BIOS will allow, and to my surprise it seemed to help. But windows desktop 2D performance seemed somehow slightly sluggish using 32M Aperture.

I have only 512M of system DDR ram, so I was hesitant to set the AGP Aperture to 512M, but went ahead and tried it anyhow. Well, the results were very good. CoD graphics are smooth now, and Windows 2D desktop performance has never been snappier.

This all is puzzling. How can setting the AGP Aperture to 100% of system ram do ANYTHING positive?

Why does 4.12 seem to favor an AGP Aperture on the extreme side of either small or large, and on a card stocked with 256mb of ram?

This seems to fly in the face of logic, ESPECIALLY considering my card has a full 256mb onboard.

System specs:

Biostar M7NCD nForce2-400 motherboard, BIOS date Aug 2004
AMD Athlon XP 2800+
512Mb DDR
Sapphire Radeon 9600XT 256mb (red PCB version), BIOS date Nov 2004
Sound Blaster Audigy 2 ZS
3Com 3C0905C NIC
WD 120g ATA100 7200rpm
LG CDRW
Win XP SP1 w/ all updates current

Ripsaw

Any comments on this? I find it a curious situation.

MindlessOath

prihttp://www.rojakpot.com/ <----read the bios guide.

AGP Aperture Size

Common Options : 4, 8, 16, 32, 64, 128, 256

Quick Review

This BIOS feature does two things. It selects the size of the AGP aperture and it determines the size of the GART (Graphics Address Relocation Table).

The aperture is a portion of the PCI memory address range that is dedicated for use as AGP memory address space while the GART is a translation table that translates AGP memory addresses into actual memory addresses which are often fragmented. The GART allows the graphics card to see the memory region available to it as a contiguous piece of memory range.

Host cycles that hit the aperture range are forwarded to the AGP bus without need for translation. The aperture size also determines the maximum amount of system memory that can be allocated to the AGP graphics card for texture storage.

Please note that the AGP aperture is merely address space, not actual physical memory in use. Although it is very common to hear people recommending that the AGP aperture size should be half the size of system memory, that is wrong!

The requirement for AGP memory space shrinks as the graphics card's local memory increases in size. This is because the graphics card will have more local memory to dedicate to texture storage. So, if you upgrade to a graphics card with more memory, you shouldn't be "deceived" into thinking that you will need even more AGP memory! On the contrary, a smaller AGP memory space will be required.

It is recommended that you keep the AGP aperture around 64MB to 128MB in size, even if your graphics card has a lot of onboard memory. This allows flexibility in the event that you actually need extra memory for texture storage. It will also keep the GART (Graphics Address Relocation Table) within a reasonable size.


SOME shaders require more agp arpriture memory, for textures needing it to increase in size, things like this would related to something like the ruby demo wrapper for ati cards. it is a demo for ATI's x800 video card, but using the wrapper it could run it on 9x00 video cards as long as you had about a gb of memory and a higher agp arpiture size to handle the shaders from the wrapper.

MOST coders wont allow that to happen for games, so thats why you set it around 64 to 128, it also makes it more stable for most systems. i was just using that to explain a bit about it.

it does make a differnce depending on the applications u use, and the way the developer made them, however with most things standard 64mb and 128mb are standard unless a special instance is needed for something unique like explained above.

also in some systems if you go to high it will cause bad problems, im not sure why, but in myne if i set it higher than 128 it will not boot and run stable at all.

----------------------------
in the 4.12 drivers, their might be some changes for things, and they may have added some openGL tweeks (direct3d too)... so this may change certain things and how gart communicates and transfers/balances loads etc. only ATI can give you the true answer to your question, and i doubt their going to to tell ya... just cause their a big compainy.

Ripsaw

I had run accross that info while googling. Not sure why my BIOS offers a 512 meg Aperture. And I know that with more video ram the aperture size can be smaller, and that's what's weird-- trying to just figure out the fluke as to why setting the aperture so ridiculously large, all of system ram in my case, makes the graphic stuttering go away in one particular OpenGL app. And it does also seem to make the Windows 2D desktop operations snappier.

Too weird.

MindlessOath

well that info in particular is kind of old. i woulndt say that it has in mind many grfx cards with 256mb's on them, and the newer 512 option for the size in bios, so mabe you can reply this on the forums at the link posted above, your info will help him out alot and mabe he will update his review or get some direct info from ATI themselfs.

eggs420

I have 1gb ram and my system is unstable with agp aperture set at 512. 256 and 128 are pretty much identical in benchmarking but in games it feels like 256 is a bit better in some of the larger maps (bf:v).

Zorg

Looks like a classic proof that the driver is written the wrong way - instead of using card's VRAM the driver is using SYSRAM to process the video code.
I was suspecting it for some time now...
I will test it with my 9600/256MB and see how it goes.

Vapor

This might actually be a GOOD thing! Imagine if they can code it properly in the coming releases and the performance boosts that will accompany it.

Zorg

You assume they can do it?! - this then would suggest they intentionally do it the wrong way to boost high-end card sales. Ati has to decide between goaling happy consumers for once in a lifetime or pushing crazy priced high-end cards. What's your bet?

virgo

I also have a 9600XT and have just tried running on a 512mb AGP setting,from my normal 128mb,and sure enough it runs without the small amount of stuttering I had

Nicky-chan

They kinda do. They hold back new cards so people buy out the supposibly new card and then when most ppl have the card they send out the next series.
But as for them intentionally doing so I dont think so. It would make no sence becuase they in compition with Nvidia and they want to have the better card so people buy there products.

I dont know if this is possible but asuming your gfx card isnt using its own memory and using the system memory insted, that would be one odd situation. O.o

Ripsaw

AH HAAAA! Eureka! I knew I wasn't imagining it. Virgo's post confirms my findings.

There's something up with the 4.12 driver in this regard, at least on 9600XT cards w/ 256mb.

Ripsaw

Have some graphic stuttering in any games w/ Catalyst 4.12 driver? Try setting AGP Aperture to 512 in BIOS and report back here with whether or not setting 512 Aperture helped eliminate the stuttering.

See this thread for details:

http://www.driverheaven.net/showthre...d=1#post525449

Chaos

I merged this since they are both by the same author regarding the same issue

Ripsaw

That's cool. Sorry for the dupe posting.

Chaos

NP, just didnt see the need for both

Zorg

As I said before - it's all about the video driver who manages the use of the video card's Vram or just using sys ram instead. Not really an odd situation - it requires code to handle the video card efficiently (or not)

MindlessOath

well i know they fixed a bug that was effecting 256mb video cards... they found a problem with it when they were testing PCI-express video cards with 256mb's and they should have produced simular results to the agp counterpart, but they were not, so they fixed the bug and they both produce simular results.

however, AGP does not have the abilties to use system ram.... other than agp arpriture which like said above, just sets aside that memory for stuff, and im sure games have to code for this sort of things (in the engine).

like i said really only ati can confirm or deny anything tho.

pir8nyc

I think I might have found a way to use this to our advantage, at least for the Half-life 2 engine.

In XP control panel, system settings, advanced tab, there is an option to set memory usage to either programs or system cache.

Now the difference is usually explained as system cache for server, and programs for a standalone pc. Well, some folks seem to have found, that for 512mb of ram or more, memory may actually be used more efficiently if set to cache. As I understand, what this does is to store the OS in the RAM and then swap out for the program as needed . Sound bad right? Well, I tried it out of desperation, and lo and behold, it works a treat with HL2, no more stuttering (other than the ones everyone gets), on 1024X768 AAX2 Aniso X2 on my 9600XT. I haven't benched it yet, but am not really concerned, as I found that benchmarks may or may not correlate with stuttering. There might be a way to duplicate this on non-XP systems, but from the little I read it involves registry hacks.

Try it, if it works do post here.

The_Neon_Cowboy

Biostar M7NCD cheap board like $50 single channel, Nforce2 400, Not ultra
512Mb DDR 1 stick god knows what latency/brand

Hmm if you'd bought a abit/asus/gigabyte nforce2 400 ultra DUEL chanel board and a brand name GIG kit of 2x512mb ram something tell me you'd have less of a problem if any at all....

BTW: you should be runing XP SP2 / AGP apiture size of 128mb

I'm not sure why you card is starveing for texture memory so bad what res are you trying to game at ? Let me guess HIGH? with AA/AF

I'd reccomend you should upgrade to 1gb of ram..... if you play games
maybe even dump the board buy something good


LARGESYSTEMCACHE = for things like FILE severs ONLY
well known for couseing HDD corruption on XP (windows @ fault)
give it a while for the "delayed write" errors to show up....

MindlessOath

im with neon cowboy with that :P i didnt bother reading your stats but now that i see it :P

dump the sound card for something cheaper and better, theirs alot better out their, i belive VIA puts out some nice sound cards at a lot cheaper prices. and get better memory and motherboard.

i have bought biostar for clients myself, but mostly its an oem group that supplies computers for compaines which dont play games or tweek things.... of course they have made strides from way back when... they still are not up to par on things such as abit/gigabyte or asus (etc...).

Ripsaw

How come you keep slamming my hardware in posts?

General consensus among hardware reviewers is that all nForce2 mobos perform within 3 - 5% of each other on the numbers, some just allow overclockability more than others. I don't OC, so no big deal there. Good thing because the M7NCD is a dismal overclocker. My main memory is Micron brand, PC3200, latency is CL3 but running it at 333mhz it handles CL2.5 ... never heard of 'God Knows' brand

Go run out and buy all new hardware, huh? No thanks. Mine is fine for what I do with it.

Dual channel with an AMD processor?... no major perf difference over single channel.

As I replied in the other post, it is OBVIOUSLY the 4.12 driver, since prior to installing it there were no, zero, zilch, nada, problems. Install 4.12 and BOOM, stuttering. But only in an OpenGL app, smooth sailing in D3D. It's a known fact that OpenGL ability is the weak link in ATI's chain, with drivers, at least when compared to nVidia, their main competition. Sorry to disappoint you, but it is indeed the driver, not my hardware. Only variable that changed was trying 4.12. And before you launch into a tirade about how I, whom you obviously believe to be a noob (yeah, right), probably screwed up the driver install and didn't properly uninstall the previous version Catalyst driver, let it be known it was thoroughly uninstalled using DriverCleaner 3, and with a manual peek into the registry to ensure no branches remained from the prior version before commencing install of 4.12. My card is not starving for texture memory, it is not a texture storage issue-- texture quality and appearance are the exact same regardless of AGP Aperture set to 32, 64, 128, 256, or 512. Just that any value except 512 causes intermittent skip and stutter in graphic scroll and pan.

P.S. It's DUAL, not DUEL; APERTURE, not APITURE; STARVING, not STARVEING; God, not god (unless you're a polytheist)... since we're obviously splitting hairs here.

Ripsaw

The DSP on the Audigy 2 ZS packs about a 4000 MIPS punch. No other sound card in the same price range can touch the processing power. My old Turtle Beach Santa Cruz had only a miniscule Cirrus Logic DSP rated @ 420 MIPS. Compared to the Audigy 2 ZS, my old Turtle Beach card is... well... a turtle.

Processing power translates to a better CPU offload, which translates to better system performance.

The Audigy 2 ZS is a highly rated card by virtually every tech site that has looked at it. I think I'll be keeping it for a bit. Creative's drivers aren't too bad, either.

MindlessOath

their are lots better sound cards out their than creative... belive me... tho i wont do the search for you, i already did do that along while ago, see for yourself dont let me convince you... genral public would make you think that its good because its popular and always will be unless they messup bad in something.

its not terrable, but for the money theirs lots better out their, mabe even cheaper stuff too.

crucial ram at CL3.0 and as low as 2.5... hrm... 333mhz... well lets say this, im still running my rig at single channel, i agree dual channel isnt much a differnce, it is but not by much. but i run a single 512mb of munshkin 2-2-2 @ 400mhz and i run circles around anything with CL2.5 and looser timings... i dont have direct benchmarks because i dare not go with my older memory ever again.

as for biostar, yes not very great overclocker, and not a plethera of options, BUT its mostly stable, even if it sacrifices speed advantages... then again its mostly an OEM hardware, meaning buisnesses are looking for only stable, and not fast fast fast.

i dont think that the motherboard is at fault here, tho you could increase speed if you change to a differnt manufacture, i would do that last, first if it were me, and i know it isnt, thats why im only suggesting.... to update that memory to something better, OCZ, munskin, and corsair all ofer top notch memory, and a CL2 is something you would most definatly want to look into! 400mhz even if your CPU doesnt go that high, cause im sure the bus can, no need to overclock at all (hrm.. tho i did put in a higher grade 3500DDR into an older motherboard and it didnt work right, dunno why, but it works in this computer im typing on, which btw is also a biostar motherboard, it was