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eva2000
03-16-06, 12:03 PM
Hmmm XFX might not be clocked as high in real 3D mode http://forums.guru3d.com/showpost.php?p=1664365&postcount=1172 ?

i have been looking into the bioses of a few of the 7900 series cards and the 7900gts, all the gts i have seen run at 1.2 volt in the bios where as gtx runs at 1.4 so i am sure when the bios is modded to 1.4 on the gts with adequate cooling of course it should in theory be able to reach a similar level on the core as gtx, the weirdest thing i saw is on the delta clocks in the cards bios my msi 7900gtx has a 50mhz value on all 3 vid values whereas the 7900gt by xfx has 0 on all values on the delta clocks and the xfx 7900gtx xxx has 15mhz value on the delta clock of the core, whereas the msi 7900gtx has delta clock of 50mhz on the core, i wonder if this is done to give them a higher core clock value, i don't know, i'd be interested to know what difference the delta clock values make

for those unfamiliar with delta clock or geometric clock on 7800GTX series they had a 40mhz delta clock so for example BFG 7800GTX rated 460/1300 in 3d mode would be 500/1300 and drop back to 460/1300 in 2d mode.

With 7900GTX, MSI has 50mhz delta while XFX 7900GTX XXX has a 15mhz delta.

If MSI 7900GTX stock core is 650mhz then 3d = 700
If XFX 7900GTX XXX stock core is 675-690mhz then 3d = 690-705mhz

so in 3d mode it might end up the same clocks!!!!!

Interesting to see what other 7900GT/GTX brands have for a delta clock value!

What if eVGA 7900GTX SC locking issues is due to the delta clock ????? what value it have for delta ???

Crazy Chuckster
03-16-06, 12:15 PM
Nibitor reports a 50mhz delta on the 5.71.22.12.02 and 5.71.22.12.06 eVGA 7900GTX SC bioses.

That very well may be the case that the delta is pushing it past its limits.

FraGTastiK
03-16-06, 12:16 PM
Well its not something you would call sneaky and absolutely not something worth raising a stink about.I guess each company can take the liberty to choose whatever delta value they think it helps the most with performance of the card and put it in their bios.They can end up being wrong with their assumption though.

You can change delta values with bios modding as you mentioned it yourself, I remember a modified bios for 7800 seires provided by one of the EVGA forum mods ( requested by users) showed that lowering or dropping the delta altogether although may result in higher Overclocks but in real world performance it actually has no advantage, delta included clocks had better results even if they didnt clock as high as no delta bios IIRC.

Looks like XFX thought it would help, that might be the case with 7900s I dont know maybe we need to do some tests again.

I dont have the the link to that EVGA forum thread with delta/no delta performance numbers right now but people from EVGA in here sure can help with that.

tieros
03-16-06, 12:18 PM
FYI, the eVGA 7900GT Superclocked has a delta of 20 listed for 2D and 3D modes.

jAkUp
03-16-06, 02:47 PM
The XFX has 15 in 3D. The BIOS is up at Mavke.

-=DVS=-
03-16-06, 03:10 PM
Just to clarify Delta adds to Geometric Domain only , so other faster cards might have low Geometric Domain but faster Rops and Shaders , this pic is from my BFG 7800GTX @ 500 MHz , because of odd dividers when you set at 500 it runs at 513 Rops/Shaders and +40 Delta for Geometric.
There was a review done in some games higher Rops/Shader might be better then higher Geometric Domain and vice versa ;)

So its not exacly a bad thing.

http://img399.imageshack.us/img399/3782/domain3yh.png

Auswak
03-16-06, 04:50 PM
FYI, the eVGA 7900GT Superclocked has a delta of 20 listed for 2D and 3D modes.


This is incorrect.

EVGA did not change the Delta Clock settings.

They are set to the default 50MHz

Thanks

:)

a12ctic
03-16-06, 05:04 PM
my 6600GT has a delta of 200mhz ;)

tieros
03-16-06, 05:16 PM
This is incorrect.

EVGA did not change the Delta Clock settings.

They are set to the default 50MHz

Thanks

:)

but...but...but... :D

http://www.logicalshift.com/images/7900gt.jpg

Dazz
03-16-06, 05:16 PM
Which program can be used to remove the delta clocks i hate them myself.

Scrach that the guy above posted one.

What program can save your current BIOS?

Auswak
03-16-06, 06:05 PM
I am sorry tieros, my mistake.

I was referring to the 7900GTX which has 50MHz

You are correct the 7900GT does indeed have 20MHz Delta as default.

Thanks

keith33
03-16-06, 06:09 PM
I am sorry tieros, my mistake.

I was referring to the 7900GTX which has 50MHz

You are correct the 7900GT does indeed have 20MHz Delta as default.

Thanks

Any luck on a GTX Superclock fix without RMAing yet? :)

Dazz
03-16-06, 06:21 PM
Pfft NVflash sux big time i was able to save the file but flashing it simply does nowt. nvflash -f filename in my case(new).rom and it just bring up the instructions why is this program so difficult to work crist flashing my X800/9800 was a million times easier and best of all it WORKED

Superfly
03-16-06, 06:27 PM
Daz - if you have the original BIOS from your card then you can just use "nvflash new.rom"

Superfly
03-16-06, 06:27 PM
By the way my XXX 7600GT runs like a charm - hehe

Dazz
03-16-06, 06:34 PM
Daz - if you have the original BIOS from your card then you can just use "nvflash new.rom"
Will that work i'll try that thanks time to reboot the PC for the 20th time today lol.

Dazz
03-16-06, 06:40 PM
That worked thanks :thumbsup:

Superfly
03-16-06, 06:43 PM
no worries

FraGTastiK
03-17-06, 04:21 AM
If a new driver is not going to fix the problem and if voltage regulators are not the contributing factor here I guess they probably end up lowering the delta for stability.