ATI HD 6950 2GB 'Dirt 3' unlock

Oh ok. So if I run Heaven for 30min and 3DMark for 30min with 1.175V and with the HD6970 clocks, and the temps are not higher than 90-95c and I don't have any artifacts, I'm safe?

Will the clocks of a HD6970 reduce the life time of my HD6950?

 

When i said 90c, I meant in something like furmark. In general gaming/3dmark 11 they should stay below 80c.


The clocks can potentially reduce the lifetime of the unit if temps are not kept in check though as the 6950/6970 are both based off the same gpu there probably will not be any noticeable decline in it's long term usability at 1.175v. Though, as always, overclocking is done at you own risk.

 

Why are you raising core voltage so much at 880MHz? My card (SKU# 11188-05-20G unlocked) is perfectly stable at 880/1325/1,110v. I tried 880MHz at stock 1,100v but after one crash during BF3, i raised it to 1,110v and no more problems. I'm not raising memory clocks above 1325MHz, because i damaged one brand new card with mem. clock at 1370MHz (i played cca one hour of BF3 and bum..restart... artefacts in windows, freezing.. the end ).

 

Well, I think it's smart to set your voltage to 1.175, since you're setting the clocks to the HD6970's standard too, so why let the voltage stay at the HD6950's standard?
1.175V Is pretty safe I think. I've seen more people using 1.175V saying that it's stable "as a rock". The most people who use 1.100v or a little above it got artifacts after two months of usage or so.

By the way, my card didn't arrive today. Probably tomorrow. I'll keep you guys up to date. And for the one's who are interested, this is my self-made guide how to do it:

Good enough, isn't it haha

 

The first rule of overclocking is to use the lowest voltage possible for the highest stable overclock. Getting permanent rtifacts is generally caused by a hardware weakness and not by too low voltage, too high voltage is more likely to cause harware issues, though 1.175v is not too high.

You would simply need to go through the motions of testing for stability before you settle for an overclock, but there's no gurentee you won't get a hardware issuw further down the line so it's important to test for stability thoroughly as failing/weak hardware will give certin indications.

In this case the memory would be the most important thing to be careful with when overclocking and there are certain indicators that can help in determining whether you are pushing it too far. To test the memory you can gradually increase it while running 3dmark11 and when your score starts to drop rather then increase you have found your memory limit as the meory has error correction and will start to correct itself when errors occur leading to a drop in scores. Once this happens you will need to reduce your memory to the prevous settings or around 25Mhz lower to be on the safe side.


Ps.

Do not modify your bios voltages with rbe until you are sure the card can handle it and most importantly do not change gpu clocks with RBE as this function doesn't work and will give you a black screen.

 

Aah. So lets say I start with 1330Mhz, and I up it with 10Mhz each time. I see at 1360Mhz that the FPS is dropping/stuttering/performance drops whatever. I set it back to 1345/1350Mhz and I'm safe?

Though one more question beside the other just written above, how can I flash my BIOS back if my card crashed? I know that I need to turn my computer off if it didn't do it himself, but do I need to set the Dual-BIOS switch to 1 while Windows is running?

How to change my gpu clocks then? Thanks for this advice btw, really appreciate that you are helping me out! I want to OC it the safe way, because for me €235,- isn't a very little amount of money.

 

Firstly there are no gurentees in overclocking but don't be scared either, these cards are generally well built and can handle decent overclocks as long as it's done properly.

For the memory, yes, once you start to see drops in performance you have reached your limit and dropping to the previous setting should ensure you have no issues. In my case I can put the memory all the way up to 1450 Mhz before I start to notice frame skipping/slowdowns but when testing with 3dmark11 I found that once the memory is set to 1400 the score actually drops slightly but at 1375Mhz the score increases, so I have settled for 1375Mhz.

To change your gpu clocks you'd have to use sapphire trixx, you can also use sapphire trixx to test higher voltages to determine if they are safe. Once you are sure on what clocks/voltages are safe you can set sapphire trixx to enable them at system startup.

Al alternative way to fo this is to use rbe to increase your gpu voltage in the bios and then either setclocks in sapphire trixx or use a toll caled 'racerx' to modify ccc to allow higher clocks.

The second method is recommended as this way your clocks will always remain at what you set in ccc and you will not need to use anyother software.

 

Oh. Well I will just continue running Sapphire Trixx then I think.

So I'm going to start tomorrow with 1330 Mhz, then after 30 seconds 1350Mhz and then 1375Mhz. If I don't see any performance drops I will keep the 1375Mhz, because that's fast enough for me.

I will tell you tomorrow the results in this topic! I hope it's going to work! Thanks for your advice so far!

I hope to succesfully clock the Sapphire HD6950 2GB Dual Fan from:

800/1250/1.100V

to

880/1375/1175V

UPDATE1: Card installed. My first GPU installed by myself; damm what a pain in the ass! I was a bit confused, because my old GTS250 was connected to my PSU with this cable, while my HD6950 uses this cable. I first used two PCI to PCI cables to connect my GPU to my PSU, but my PC wouldn't start. So I unplugged it and used the Molex ones.
But.. One problem, after installing the drivers etc., my display seems kinda unsharp, and I didn't have that with my old GTS250. Will take a look at that problem. Though my shaders were immediately unlocked to 1536 Unified!

UPDATE2: Auto-Adjust did the work.. Sharp as normal! Now to the overclocking part.

UPDATE3: I succesfully clocked the card to 850/1350/1.150V. It feels safer to me, I don't know why. No performance drops or anything, but if my GPU gets dated I will OC it further. Enough for now I think.

 

I discovered an issue by the way. Why does dxdiag show 240MB GPU memory while I have 2GB? Sapphire TriXX does show 2048MB. And... Assassin's Creed Revelations and Skyrim are playing smooth on maxed out, but sometimes it does stutter. Is this an unstable-GPU-issue?

 

I'd ignore dxdiag, it shows my gpu memory as 1740Mb. Use msi afterburner to view actual vram usage while ingame.

 

Aah ok. And what about the AC Revelations & Skyrim stutters?

I runned a maxed out Heaven benchmark by the way, and at 99% GPU load it didn't come above the 73 Celsius and idle it's about 45-50 Celsius with 875/1375/1.15V. Safe enough?

 

it's your cpu most likely, otherwise make sure you use the latest drivers and don't have anything running in the background. Also see if turning down settings improves with the stutter, could just be too high settings for the card.

 

I received my 6950 Dirt 3 Ed. about a week ago. I flipped the switch before installing, and GPUz showed a successful unlock with 1536 shaders. I have my core set at 900mhz with 1.175v, but I'm hoping a lower voltage will suffice. My memory won't go higher than 1350mhz - anything over that and my card has some strange split screen effect.

Good luck people!

 

Could someone upload manufactures orginal unlocked bios please?
I got 220SA / 50G version and no matter what i do I get stuck with 1408 shaders ... this is the last thing I want to try ... just the orginaly moded bios

Thanks

 

Here is mine :
http://www.multiupload.com/4JYRWXGSVM

 

This card is soooo sexy !

 

Very true statement, it looks gorgeous IRL

 

I want a Sapphire 6950 toxic OC, but I will wait to see the 7000 series performance before buying anything

 

Just got a friend to buy the card on newegg just a 2 days ago. Flipped the switch 1408 -> 1536 easy pie. Gave her a .reg file from RacerX to up the limit to 1000/2000 so now its running @880/1375/1.1v stock. So far so good, not bad for $279 easy unlock. (not saying all cards unlocked, just the specific place/time)

 

I have a 6950 Dirt 3 Edition That I have not managed to unlock the shaders.
Would you please give me your BIOS?
(I ask you because I want a newer BIOS version, and you've bought your 6950, not so long ago)
I would appreciate it very much.