7800 GTX BIOS - 50 delta - mem timings

[HeavyH20]

Here are two modifed BIOS files I am currently using. After much testing, I think it is ready to share. There are some basic mods, nothing radical, but the small tweaks have added up to improve card performance.

First, the rev4-500.rom has the default clock at 500 with a 50 Mhz delta. It is agressive, but great for water cooled cards that can handle it. The 50 MHz delta improves the vertex to shader/ROP fill rates at the higher clocks. The second file, rev4-473.rom is the same, but starts out at 473 for those cards that may not get to 500.

Second, the memory has simply been bumped to 1350 and 1300, respectively.

Third, the 3D throttle is at a whole multiple of 27 Mhz (432) and uses a 40 MHz delta versus the 35 stock. Transitions in and out of 3D are a little smoother, so that when you are close to the edge, you are less likely to experience any issues like a freeze.

Fourth, the memory timings have been tightened as such to improve memory bandwidth, but not affect OC ability. I saw around a 120 point increase on 3Dmark05 with this alone, clock for clock (results below).

All in all, this BIOS has improved my default driver settings (quality, application controlled for AA, AF) to 8900 in 3Dmark05 with my CPU at 2.5 Mhz. With a little tweaking on the driver settings (no LOD cheat), and a small OC bump to 2.65 GHz, I was able to get 9600. I am looking to exceed 10K with basic watercooling an x2 AMD CPU, but the CPU is a couple of weeks away.

It is built on the 5.70.02.11.XX BIOS build. I found it had a number of BIOS bugs resolved.

The test system:
AMD 64 3200+ @ 2.5 Ghx
BFG 7800 GTX OC@ 500 Mhz/1350 default
81.82 driver
All default drivers settings, no tweaks

Core Delta Tests, card at 1350 memory

All 3DMark05 results

Clock____0 Delta_______40 Delta_______50 Delta
490_______8347_________8570__________8593
495_______8397_________8588__________8603
500_______8451_________8728__________8772
505_______8475_________8764__________8781
510_______8534_________8769__________8823
513_______8569_________8803__________8847
520_______8577_________8805__________8864
525_______8703_________8852__________8921
527_______8710_________8912__________8980
530_______8728_________8935__________9045
535_______8765_________8983__________9078
540_______8824_________9034__________9123


Memory Speed Effect

Core at 500 Mhz plus 50 delta

Memory Clock________3DMark05_____
1200_________________8441_______
1250_________________8568_______
1300_________________8706_______
1350_________________8792_______
1400_________________8893_______
1420_________________8908_______
1440_________________8945_______


Memory Timing Change Testing results

Core at 500 Mhz plus 50 delta

________Stock___Mod
1350____8792____8985
1440____8945____9090

Here is the spec and changes on the memory:

Samsung GDDR3 1.6 Specification

K4J55323QF-GC16 / K4J55323QG-BC16



________SPEC__Change______________________________ ___________

tRC______27_____24_____Row cycle time(min) - operation (tCK)
tRFC_____34_____32_____Row cycle time(min) - Auto Refresh (tCK)
tRASmin__19_____17_____Row active minimum time (tCK)
tRP_______8______7_____Row precharge time(min) (tCK)
tRCDRD___ 9______8_____Ras to cas delay(min) for Read (tCK)
tRCDWR___5______5_____Ras to cas delay(min) for Write (tCK)
tRRD______7______6_____Row to row delay(min) (tCK)
tGR_______2____________Gapless 2 tCK
tRTW_____12___________Read to Write at same bank - CL=8tCK, tCDLR=4tCK
tRASmax__100000________Row active maximum time (tCK)
tRCDRD____9____________Ras to cas delay(min) for Read (tCK)
tRCDWR___5_____________Ras to cas delay(min) for Write (tCK)
tWR______5_____________Last data in Row precharge (7 tCK)
tCDLR_____4____________Last data in to Read delay (6 tCK)
tCDLW____0____________ Last data in to Write delay (0 tCK)
tCCD______2____________Column address to column address delay (3 tCK)
tCKmin____1.6___________Clock minimum cycle time (ns) - CL=8
tCKmax____6____________Clock maximun cycle time (ns) - CL=8

Register timings on the 7800 GTX (default is timing set 7)

0813211B

0A01060A

20270509

The new settings register values:

07112018

0A01060A

20260508

If you are curious about the history, here is the thread:

http://www.xtremesystems.org/forums/...ad.php?t=72638

BTW, I have tested the BIOS file on an eVGA GTX KO, XFX GTX EE, ASUS TOP, ASUS GTX, BFG GTX OC, and a regular eVGA GTX. All showed improvements.

The files have been fully scanned for viruses, spyware, etc then zipped.


The BIOS clocks:

Rev4-500.rom 500/1350
Rev4-473.rom 473/1300

[Nanometer]

Good work, I remember the days when i modded my 5900 128meg's bios to claim first in 3dmarks 03 and 05. have you tested this bios with any games? or just 3d marks?

[Tibu]

Wow if this could be done for a 7800 GT, it would be awesome. Could you release a BIOS that has the memory tweaks for the 7800gt? I realize a GT would not get the same overclock, but what a=bout the timing tweaks? Could a GT handle that?

[eva2000]

ok seems like a bios my BFG 7800GTX Stock heatsink card would like as it does 528/1411 rivatuner on stock heatsink air for 9,542 3dmark05 right now

can i do the flash with batch files (helps on blind flashes)

i.e.

to backup file i put these in backup.bat on dos floppy

nvflash -b original.rom

to flash bios to modded put these into update.bat on dos floppy

nvflash -5 -6 modded.rom

to restore to original bios put this into restore.bat on dos floppy

nvflash -5 -6 original.rom

then boot to dos floppy and type

backup

then

update

????

[Vapor]

May I make a recommendation for the mem timings? I say set TRC to 24 (as it should be....tras + trp) as it will probably provide more stability....if it doesn't drop tras to 18 and set trc back to 25.

[HeavyH20]

Makes sense. I will try those memory timings and modify as needed. I will also run some more tests to confirm stability. I will post back later. Good catch, BTW. It was at 18 -7, then I dropped it to 17 - 7 to test with success, but did not revisit TRC.

EDIT:Mem timings run and tested. Good results. Links updated. I also included a 473/1300 clock version since some people may not have a card that gets to 500/1350.

Here are some 3DMark05 results with the rev 4 500 BIOS. All default driver settings, 81.82, AMD 3200+, 10x multi.

2.0 GHz - 8326

2.1 GHz - 8526

2.2 GHz - 8650

2.3 GHz - 8735

2.4 GHz - 8857

2.5 GHz - 8985

[eva2000]

so my batch file method okay HeavyH20 ??

[HeavyH20]

Looks fine, but command should be nvflash -j -4 -5 -6 Rev4-500.ROM to flash. And, I usually make a separate floppy with the file in an autoexec.bat file so it auto executes if you ever need to flash in the dark. Just have to hit "y" after you see the floppy light stop, wait for it to stop for a bit once more, and reboot back to stock. But, I just practiced that with my monitor off. Just in case

I have flashed my card around 30 times with different BIOSs to test. Never had a failure yet. Pretty straight forward. But, you should always have your stock BIOS backed up.

[HeavyH20]

Wow if this could be done for a 7800 GT, it would be awesome. Could you release a BIOS that has the memory tweaks for the 7800gt? I realize a GT would not get the same overclock, but what a=bout the timing tweaks? Could a GT handle that?

I am working on that next. Same tweaks, just GT based. But, since I had the GTX, first hand testing help quite a bit.

So, GT BIOS with a delta (45 seems to be the right one), fan speed changes, memory timing mods, and anything else most card will handle. I will post back in a bit with the GT version.

[Rammsteiner]

Hello,

Great work on the BIOS! But Ive a MSI 7800GTX what wont go higher as 470/680. Will this BIOS work on this card? Would I see any improvements because of the delta being only good at higher clocks? Ive still stock cooling, but not planning to change that (yet) .

[Vapor]

You would like the 473/1300 version and underclock when you boot and leave at stock when you benchmark.

[mdzcpa]

Excellent work! I'll try these out.

[Rammsteiner]

Cool, but when I posted the 'new' BIOS wasnt there yet, anyway, great work though! Might try it . And OC the memory ofcourse

[Rammsteiner]

NOOO, I didnt installed the BIOS yet because I wanted to test if it can handle 473Mhz... NO, it cant... Thats a pitty. Do I still have better performance if I run it at 470Mhz with this modded BIOS compared to my original BIOS?

[HeavyH20]

Cool, but when I posted the 'new' BIOS wasnt there yet, anyway, great work though! Might try it . And OC the memory ofcourse

Yes, I posted a second version for those cards that are air cooled. Still a steep spec, but most should make it on stock cooling. I have tested this on a stock card.

BTW, here is a link to a survey I have been tracking on GTX OC levels, stock, mod, water, vapo, etc. I wanted to get plenty of stock results, and XS is not exactly the best place for that, is it ?

http://www.hardforum.com/showthread.php?t=945092&page=7

Post back any results!

[HeavyH20]

NOOO, I didnt installed the BIOS yet because I wanted to test if it can handle 473Mhz... NO, it cant... Thats a pitty. Do I still have better performance if I run it at 470Mhz with this modded BIOS compared to my original BIOS?

So, no go on 473. You are probably limited by the ROP/Shader component of your core.

At 473, there is a significant bump to 486 from 459. Stick with the stock BIOS. You will lose the benefits of the 50 Mhz delta, since the ratio between physics and fill needs to be maintained. So, at lower clocks (<473), the 50 Mhz delta advantage goes away. At 473, the vertex is at 523(<513), and the ROP/Shader at 486. This represents the next big bump in performance. 473 was kind of the minimum that would show an improvement with a bigger delta, anyway.

[Rammsteiner]

So, no go on 473. You are proabably limited by the ROP/Shader component of your core.

At 473, there is a significant bump to 486 from 459. Stick with the stock BIOS. You will lose the benefits of the 50 Mhz delta, since the ratio between physics and fill needs to be maintained. So, at lower clocks (<473), the 50 Mhz delta advantage goes away. At 473, the vertex is at 523(<513), and the ROP/Shader at 486. This represents the next big bump in performance. 473 was kind of the minimum that would show an improvement with a bigger delta, anyway.

Ow, well, good work anyway. Maybe some better cooling might work out for me . But good work anyways

[Tibu]

Well ima try this out soon enough it seems:

BFG 7800 GTX

[shadowing]

Does the lower ram settings allow lower core clocks and ram clocks? Or does it allow about the same as the default?

[Tibu]

Can someone direct me on how to actually flash my card step by baby step? I've never changed the BIOS of a video card before and I must say I'm sorta freaked out about fuxoring up my brand new bfg 7800gtx. I know this may sound noobish but I just had to ask. Any help will be greatly appreciated.

[PlatoonSgtElias]

Hey can someone make me a 500\1400 bios of this bios. And 500\1500 and 550\1500. I thank you very much

[FireDragon]

Hey can someone make me a 500\1400 bios of this bios. And 500\1500 and 550\1500. I thank you very much

why dont you get a bios editor and change them your self it is VERY VERY easy to change clocks on a vid card bios...

Dragon

[maverik-sg1]

I am struggling with the timings and teh setting of with my GTX's - I am unable to use the BIOS that you have posted here (get throttled results for some reason?) - although they sound sweet.

Checked my ram timings with Nibitor and it shows me as have set0 which are really tight (compared to set7) this limits my overlock to 1500mhz (with up to 2.8v in the ram)

If I stick with the BIOS I have now and try to add the memory timings myself - how do it? What tools will I need?

Cheers

Mav

[CruSifiXken.Be]

Can smebody make a Bios with better timings for a 7800Gt?

[HeavyH20]

I am struggling with the timings and teh setting of with my GTX's - I am unable to use the BIOS that you have posted here (get throttled results for some reason?) - although they sound sweet.

Checked my ram timings with Nibitor and it shows me as have set0 which are really tight (compared to set7) this limits my overlock to 1500mhz (with up to 2.8v in the ram)

If I stick with the BIOS I have now and try to add the memory timings myself - how do it? What tools will I need?

Cheers

Mav

The OVP is probably kicking in. Here is the tweaked BIOS with a 2D, 3D and no throttle setting. It will take care of being stuck in throttle mode.