GTX285 various mods.. which may work for GTX260/280/295 also

[NapalmV5]

*** please mod at your own risk ***

voltages/vmods/cap mods @ evga ssc 285





10v 1500uf rubycon blackgate nx cap @ vacant C561-4

dont mind the bottom cap


guide to 1.39375vgpu max (reference voltage) past this voltage further vmods are needed.. crotale vgpu/ocp mods: http://www.xtremesystems.org/forums/...d.php?t=220607

these steps + crotales vgpu/ocp mods: 1.67vgpu @ load reached on the ssc 285

before attempting any vmod please measure your current voltage/s

measure points
- red:vgpu/green:vmem
- courtesy:CryptiK


note: voltages/vmods @ evga ssc 285

step #1
- for better understanding please check dengyongs post #80 cryptiks post #112 and #118
- simple way to increase vgpu from 1.15v reference
- 1.26vgpu @ load (1.3vgpu on the evga ftw 285)


step #2
- vdiff mod
- increases efficiency
- the lower the resistance at this resistor the higher the vgpu allowed
- best if resistor replaced with a 300-400ohm resistor
- or try a 700ohm resistor in serial to the 700ohm resistor onboard
- or pencil the resistor to bring resistance down to around 350ohm
- 1.29-1.33vgpu @ load (1.36vgpu on the evga ftw 285)


step #3
- one more vgpu mod
- increases voltage according to the resistance @ vdiff
- solder a 150ohm resistor to ground from this red point
- 1.36vgpu @ load (1.39vgpu on the evga ftw 285)


^ 2.20vmem @ load

these steps + crotales vgpu/ocp mods: 1.67vgpu @ load reached on the ssc 285


thanks goes to
- Cryptik for all the help/confirmations
- crotale for his vgpu/ocp mods
- dengyong, andressergio and everyone else contributing @ thread

[Stelios]

Interesting ... Thanks for sharing !!!

[bito]

I wonder if having an eight pin power cable in place of the 2nd six pin would help any ?

[dengyong]

Thank you for sharing.

[Orangeblast]

Outstanding, thank you for this.

Where did you get your SSC from? Newegg...Mwave...Tiger??

[dengyong]

Originally Posted by Orangeblast

Where did you get your SSC from? Newegg...Mwave...Tiger??

Would that make a difference ?

[NapalmV5]

i got my ssc from newegg..

which gtx285 brands @ 4908 pcb ?

[Orangeblast]

Originally Posted by dengyong

Would that make a difference ?

It might...never know.

[Orangeblast]

Originally Posted by NapalmV5

i got my ssc from newegg..

which gtx285 brands @ 4908 pcb ?

Not sure, that might be mfg. specific. XFX and BFG have different PCB numbers? Can anyone check? It also might just be a batch number to a set of PCBs...anything is possible.

[NapalmV5]

evga ssc @ 1.20v
my ssc @ 1.23v
vmod @ 1.26v

no oc gain

vgpu mod does not work on the ssc until ovp is removed/increased

so if anyone could/would share that would be greatly appreciated

[TheKarmakazi]

Originally Posted by NapalmV5

evga ssc @ 1.20v
my ssc @ 1.23v
vmod @ 1.26v

no oc gain

vgpu mod does not work on the ssc until ovp is removed/increased

so if anyone could/would share that would be greatly appreciated

I think everyone is looking for OVP for these 285/295 cards... Tough to find though. From what I gather the best way to increase Mhz is better cooling. with a 295 @ 1.26-1.3v (OVP/OCP kicks in around 1.3) on stock cooler you can get about 750-775 core. With watercooling people have been getting 800-830. I imagine once we can get our hands on some Tek5.0 slims and LN2 these babies we will see big gains in the core clocks

[NapalmV5]

yeh 1.3v ovp


heres the 285 vcore mod by Dural @ luxx forums:

http://www.forumdeluxx.de/forum/show...postcount=1340


22k fixed resistor gets 1.26v on my ssc

[NapalmV5]

deleted

[SAE]

Don't ya cool these memory and pwn parts originally touched by the stock HS?

What did the last mod gain you in clocks?

[Slovnaft]

wow, i'd be scared to kill my board with that much capacitance.
jesus.

[Orangeblast]

this is fantastic. I can't wait to try this out on my 2 SSCs

[phinix_mike]

wow... nice...

[persivore]

I think you would be much better using low value (~100nf) distributed capacitance in high load areas to catch spikes and high frequency noise than addling large ammounts of bulk capacitance to the outputs of the regulators, especially with the long lead lengths which it looks like you're using. Using long lead lengths will increase ESL and ESR of the capacitors and will likely negitively effect the response of the voltage regulators.

[NapalmV5]

yeh i agree persivore.. this was just the first recap.. more recapping to come

the capping on the back of the card ^ at first i used 4 x 6.3V 470uf blackgates

but the 4 x 10V 1500uf blackgates/results @ 1st ^ post is what made me post the mod up

im looking into tantalum/film caps aswell

there are more components in the way of this recap which are deemed to be replaced

for an sli/trisli setup id recommend 4 x high quality 10V 330uf tantalum caps @ C561-4.. if you got the space for electrolytic caps go ahead

at the moment i dont recommend the recapping of the 8x100uf.. i need to recap some more.. when i do find the better the caps/capacitance ill let you guys know.. still experimental

the memory runs fine @ 1500 naked cooled just by the airflow

having said all that im playing ETQW @ 800/1750/1500

20mhz core +
50mhz shader +

the hr03 cooler itself @ idle is only about 1 C better than the stock cooler.. @ load probably 2-3 C

[largon]

^nVIDIA skimping on memory vDD and vDDQ chokes. No surprise.
tsk-tsk...

But good to see they put some sense in the layout of GTX285's vGPU VRM area after the mess on GTX260/280s.

[CryptiK]

Nice work Napalm, thanks for sharing. Those 4 x 6V-10V 1500uF blackgate caps have a huge can size for 1500uf. I suppose that's one of the benefits of using high quality audio caps. The lead length is a worry though, if you can reduce that perhaps the results will be even better. I have some Sanyo WG's and Rubycon MBZ's that may be suitable for this mod.

It's also somewhat surprising that the HR-03 is only marginally better than the stock cooler.

[NapalmV5]

sure as persivore stated shorter leads would benefit even more.. but space on the card is a beatch.. not only that but the ram on the mobo is in the way aswell

yeh its the nx 10v 1500uf bgs.. sounds as good as it performs on the 285

[ChinStrap]

Originally Posted by NapalmV5

how much gain ? ill find out later today

waiting like a little kid @ xmas. :P

[NapalmV5]

lol ok ill get to it in a moment..

i was trying to get true120 copper on.. it fits!

though ill go back to hr03 after this test run

[SAE]

Dayum... I can hear that card moan because of the weight on its shoulders (and maybe because of pimped guts that got no chance to "heal" yet ).