What is the safe Max voltage for GDDR5?

[MaxAwesome]

Hello guys,

I'm fine tuning my overclock on my HD 6950 flex, and I'm using the Trixx Mod 4.0.4 which allows me to control the Vcore for the GPU, and also the memory voltage.

At stock, the VRAM is at 1.58v. Trixx allows me to go as high as 1.8v.

Should I leave it alone, or should I push my memory a little further?

 

[Mathragh]

I'm also wondering the same thing.

My 7950 has its ram voltage at 1,6V, and I have lots and lots of headroom, but as the voltage is unlocked, it would be great to know where the limits at.

I suppose 5-10% overvolt should be reasonably harmless, but I honestly don't know. Temperatures also matter a great deal I guess.

 

[ne6togadno]

before you play with mem voltage be sure that mem has good cooling. a lot of coolers although they look like they cover whole pcb actualy contact only with gpu.
max voltage dependes from manufacturer of ram.
i daub you will get big gain from ocing memory. bottleneck of your card is what gpu is capable of then memory parameters

 

[MaxAwesome]

Well, the HD 6000 series was actually somewhat bandwidth starved, and with VRAM overclocks I can see gradual gains in benchmarks and some gains.

Even though I agree that the most performance comes from OCing the core.

But still, is there a voltage that is agreed upon as being the safe limit?

 

[MaxAwesome]

Any more opinions out there?

 

[ne6togadno]

http://www.sapphiretech.com/presentation/product/?cid=1&gid=3&sgid=1041&pid=1099&psn=&lid=1&leg=0
256bit bus, 5ghz, 2gb cant see what you can ask for except if you are playing on 3+ monitors

with computer chips there isnt anything like save limit. what is ok for 1 chip doesnt mean will be ok for next chip on the dye.
wiki says ddr5 is based on ddr3. working volatege of ddr3 is 1.5v so anythinga around ±0.2v should be ok. but check if radiator is attached to ram as well. with summer coming you dont want toasted ram.

 

[Zubasa]

You have to be careful when OCing VRAM, without proper cooling or too much voltage will kill the memory very quickly.

 

[radrok]

You have to be careful when OCing VRAM, without properly cooling or too much voltage will kill the memory very quickly.

Agreed, I would not fiddle with VRAM voltage wise, you can get permanent artifacts by doing that. Not worth it.

 

[Aquinus]

Well, the HD 6000 series was actually somewhat bandwidth starved, and with VRAM overclocks I can see gradual gains in benchmarks and some gains.

That's definitely not the case with my 6870s. Memory bandwidth actually has the smallest impact on my GPUs, where most performance can be had with a core overclock.

 

[d1nky]

ive noticed that when overclocking core, I only see a slight gain when my memory gets beyond 1750mhz, and that needs 0.010 more on volts. anything pass that and itll shut down when benching. most cards have some kind of limit before you need to up voltage anyway, and you will hit that before needing extra voltage

smash the back doors of the core is what I recommend, ive seen and read about many people killing there cards with too much mem voltage and now have permanent artifacts!

 

[MaxAwesome]

Alright, you guys convinced me. I'm leaving VRAM voltage alone

 

[purecain]

@MaxAwesome- good choice... gddr5 is delicate...
+0.5v should be ok though....

edit# +0.050 is about as much as I myself have ever increased gddr5 voltage...

I would use 0.005 increments to find an adequate setting...

good luck...

 

[Mathragh]

@MaxAwesome- good choice... gddr5 is delicate...
+0.5v should be ok though....

I suppose you mean 0,05V? =D

 

[d1nky]

haha yea don't go putting an extra 0.500v

I been upto 0.010v for higher clocks but didn't see any gains from it

 

[The Von Matrices]

Almost always it's not the DRAM that is the limiting factor for the memory clock frequency but the memory controller or the traces on the PCB, in which case increasing the memory voltage would do nothing.

 

[Velvet Wafer]

didnt knew there was a way to influence the memory voltage on a reference 6970
(volterra reg)...i would be happy if someone could show me how to do that, im upgrading to a 7950 anyway in a week