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simwiz2
04-15-04, 09:29 PM
Can anyone explain how the NV40 is scoring so much higher than its theoretical maximum in x-bit's fillrate test without color writes?

http://www.xbitlabs.com/images/video/nv40/fillrate_gif/fillrate_nocolor_z.gif

Disabling color writes we switch the NV40 into a mode where the graphics processor calculates 32 Z values per clock cycle, that is, the fill-rate doubles. However, the results don’t comply with the theory – the NV40’s fill-rate should be about 12,800 MPixels/second, while the test produces results around 20,000 MPixels/second. By some reason, the GeForce 6800 Ultra shows higher results, than the theoretical maximum!

http://www.xbitlabs.com/articles/video/display/nv40_18.html

ragejg
04-15-04, 09:31 PM
Alien technology, I'm tellin ya!! :p:p

Seoulstriker
04-15-04, 09:32 PM
it's that good. ;)

GlowStick
04-15-04, 09:56 PM
Well, isnt there alot of times where theoretical and tests never match up? I do agree, usually the theortcial is higher, and reality is lower, so that is odd.

However, i didnt know that this 32x mode is kicked in automaticly, that is pritty cool.

Nv40
04-15-04, 10:04 PM
Alien technology, I'm tellin ya!! :p:p



hehe... yep

they captured an ALIEN ,and forced him to design somethig in the NV40.. it will be nice to have such big improvements in performance in real game play :)

Daneel Olivaw
04-16-04, 12:04 AM
Area51 I tell ya. NV40 was found in a weather balloon at Area51.

bkswaney
04-16-04, 01:02 AM
The NV40 was built by aliens and dropped off so all they had to do is copy it and put it on the market. ;)

It's nvidia's way of kicking ati in the nuts this time. "lol" :D
:kill:

Edge
04-16-04, 01:15 AM
Jesus, so...much...fillrate...

Man, so you can run the card at what...8,000x6,000 now :eek:

AthlonXP1800
04-16-04, 01:35 AM
Area51 I tell ya. NV40 was found in a weather balloon at Area51.

Weather balloon? That was from Roswell 1947. :p

NV40 was found inboard GPU for the newest F-22A Sealth fighter just recently dispatched from Area 51 to AFBs available for the public. It will be ready for combat duty readiness in beginning of 2005. :D

http://www.fas.org/man/dod-101/sys/ac/f-22-19990601-f-0000l-001.jpg

ninelven
04-16-04, 01:40 AM
The F22 is much sexier than the JSF.

bkswaney
04-16-04, 01:57 AM
The F22 is much sexier than the JSF.


For sure.... Add thrust vectoring of 20% on the engines and supercruise with stealth
and u have the badest fighter on earth. ;)
Well, with the most advanced radar-electronics to boot. :D

Nutty
04-16-04, 08:08 AM
Well, isnt there alot of times where theoretical and tests never match up? I do agree, usually the theortcial is higher, and reality is lower, so that is odd.

However, i didnt know that this 32x mode is kicked in automaticly, that is pritty cool.

Of course. Whenever you write only Z or only Stencil, the card will write 32 pixels worth per clock. Twice the fillrate of colour writes. This is why the card is gonna rock in Doom3 which does a Z pass 1st, and stencil passes for every light.

Smokey
04-16-04, 08:45 AM
Of course. Whenever you write only Z or only Stencil, the card will write 32 pixels worth per clock. Twice the fillrate of colour writes. This is why the card is gonna rock in Doom3 which does a Z pass 1st, and stencil passes for every light.

I think someone is going to upgraing their Geforce4 soon :clap:

GlowStick
04-16-04, 10:57 AM
Of course. Whenever you write only Z or only Stencil, the card will write 32 pixels worth per clock. Twice the fillrate of colour writes. This is why the card is gonna rock in Doom3 which does a Z pass 1st, and stencil passes for every light.
Wow, that dose sound pritty cool, i allways thought that the programmers had to write code special for that gpu to make it kick into the mode, but that is pritty cool! If nvidia can magicly get doom 3 and hl2 on the shelves before the previews of the R420 come up, they will make a killing!

Nephilim
04-16-04, 10:59 AM
I think someone is going to upgraing their Geforce4 soon :clap:

Yeah, I'm already saving my pennies too. Gonna relegate the FX5900 to the fiancé's computer :)

Lezmaka
04-16-04, 11:46 AM
They didn't seem to say what app they used to test the fillrate.

Dave over at B3D used MDolenc's Fillrate Tester and got 11749.8 for z-pixel rate.

http://www.beyond3d.com/previews/nvidia/nv40/index.php?p=18

5150 Joker
04-16-04, 12:13 PM
For sure.... Add thrust vectoring of 20% on the engines and supercruise with stealth
and u have the badest fighter on earth. ;)
Well, with the most advanced radar-electronics to boot. :D

Yeah but can it do my laundry and fetch me coffee?

Nutty
04-16-04, 06:13 PM
Wow, that dose sound pritty cool, i allways thought that the programmers had to write code special for that gpu to make it kick into the mode
No, its automatic.

I think someone is going to upgraing their Geforce4 soon
Oh yes.. :)

jolle
04-17-04, 09:38 PM
Might be that rumoured "virtual pipelines" via VS units that was floating
around a while back..

Something like this, 32pipes + additional 16 = 48..
48 pixels per clock at 400Mhz = 19200 MegaPixels/ sec..
the benchmarks shows 19800, which is pretty close..

Dunno tho...

EDIT
On the subject of what tool they used, sounds like something called Fillrate Tester

Fillrate Tester opens our cycle of synthetic tests by measuring the scene fill-rate speed and the speed of executing pixel shaders.

bkswaney
04-17-04, 11:20 PM
Yeah but can it do my laundry and fetch me coffee?


For what it cost it should. "lol" :D

Skinner
04-18-04, 12:39 PM
Is this the mentioned 32x0 thingy ;)

jolle
04-18-04, 07:42 PM
Is this the mentioned 32x0 thingy ;)
not really, but sortof.. hehe..

it was expected to hit 12800 MP/sec since it would run 32x0 with
just Z-writes..
but instead it got 19800 Mp/sec.. which is more like 50x0 or something..

where that came from, noone seem to know..
it can be a anomaly in the benchmark, or some feature in the NV40..

speculations are going on over here:
http://www.beyond3d.com/forum/viewtopic.php?t=11659

Dazz
04-19-04, 02:38 AM
Most likely the benchmark diesn't correctly pick it up.

jolle
04-19-04, 02:58 AM
Most likely the benchmark diesn't correctly pick it up.
the scores for 9800XT and FX5950Ultra is right on the money..
which does make it a bit harder to just discount the result..
but yeah, it could be some error...


One thing i find a bit amusing about the entire thing, is that my 2 most stupidest
ideas about it, could be linked into some sort of logic..

First i thought about the romour of it being able to use VS units as virtual pipes.
http://www.theinquirer.net/?article=14878
Now, everything else in that link was totally wrong, hehe, and the inquirer isnt
know for their accuracy in.. well, the truth..

Anyhow, if you want to get a theoretical peak above 19900 MP/Sec this will
fit, 32+18 * 400Mhz = 20.000 Mp/sec..
to get those extra 18 tho, the VS units would have to push out 3 pixels each
per clock, and well.. it all seems pretty out there..

my second thought was some sort of similar feature to ATIs Overdrive..
but after checking the numbers, at 32x0 it would have to run 625Mhz to
hit a theoretical peak at 20.000 MP/sec..
and from 400Mhz that is just out the question..
altho now Albatron announces their 6800Ultra with a 600Mhz core, which
makes it a tad less incredable..
but there is still the fact that this "anomaly" only showed up in 1 test and
alot of other stuff that makes it to farfetched to concider..

The most likly theories are the ones tossed around over at Beyond3d, which
from what i understand is basicly the pipelines putting out 3 pixels per clock
instead of 2 when dealing in Z only, no color..
so 32x0 +16...

Looking forward to seeing the final word on it tho, might take a while..

Mike Johnson
04-19-04, 03:17 AM
mig 1.42
sukhoi s-42

sexy counterparts of the sexy f-22 :)