Extremely Technical Question

[Dracas]

Anyone know which AGP register to edit in the nVidia GeForce 4 Ti4200 BIOS (Chaintech-Excel Co. LTD.) to enabled 'Above 4GB Transfer Rate', these cards support these features, but it appears in many GeForce 4 Ti's they have this feature disabled, which seriously bottlenecks the 'lightspeed' memory architecture.

Anyone know how to cut the neck off the bottle, so to speak?

[$1500-P4 gamer]

Originally posted by Dracas
Anyone know which AGP register to edit in the nVidia GeForce 4 Ti4200 BIOS (Chaintech-Excel Co. LTD.) to enabled 'Above 4GB Transfer Rate', these cards support these features, but it appears in many GeForce 4 Ti's they have this feature disabled, which seriously bottlenecks the 'lightspeed' memory architecture.

Anyone know how to cut the neck off the bottle, so to speak?

Sounds extreemly risky to me. :eek:

[Bigjakkstaffa]

Yeah - where did you hear of this "bottleneck" may i ask??

--Jakk:t

[OpK Chowdy]

i'm confused. :x

[causticVapor]

The LMAII compression on many GF4 cards is seriously bottlenecked with a hardware setting?

If this is true, then I would wonder how the GF4 cards would stack up against the new ATi cards in horsepower with this "feature" turned off.

[AllGamer]

have you tried those extreme nvidia tweakers yet?

[Bigjakkstaffa]

If this was so im sure nvidia would have had some kind of sotware setting somwhere to enable the user to override it :confused:

--Jakk:t

[Dracas]

>4GB Addressing won't work in 32-bit App/system mode and only <4GB Addressing is avaible.

Now this is strictly theoretical from research, but I believe if you're using 64-Bit WinXP you shouldn't have any problem enabling the feature through registry or BIOS hacks right?

Thats the sucky part, sure you can get 8.8 GB of bandwidth maximum threshhold, but if you can only address less than four gigs of that at a time, you really aren't getting much more then 4.0 gigs max transfer at a time, its why nVidia's bandwidth claims are dumb as hell.

But apparently to get <4GB addressing going you need to be able to run 64-bit

Blarg, I can't wait till the Opterons come out, we'll all see a happy lessening of bottleneckage.

x68-64 :x Gimme

[Ammok]

Gone straight over my head.:confused:

[RobRich]

The memory mapping model of the GF chipset has nothing to do with bandwidth. The above 4 GB option is for professional users (think Quadro) that have Intanium workstations (+ Opteron in future) with greater than 4 GB of memory. This is an option of the AGP controller found within the chipset northbridge controller. The video card can only support the option if the AGP controller supports the option. For supported chipsets, both hardwere register flags at both the graphics controller and AGP controller must be set to enable this option.

The AGP controller allows for texture storage, but it must map the textures into system memory according to chipset/processor/os limitations. This means that a workstation equipped with greather than 4 GB of memory would have to have this option enabled for best performance, otherwise the AGP controller would have to wait for free address space under the 4 GB boundary layer before performing a texture operation (read, write, move). The chipset retains priority rotation (after process of course), thus system data is operated upon first. This means if system data is saturating the <4 GB memory sub-section, that the AGP controller would have to go into a PCI waitstate (stall) before the texture operation could be processed and stored, thus leading to a decline in system performance.

Robert Richmond

[Dracas]

Thanks for clearing that up :)