Topic: flashing a 6950 with 1GB using the 6970 with 2GB BIOS (Read 18902 times)

I've done it with an XFX 1GB 6950 - it allowed me to flash properly but didn't have any luck unlocking shaders.  From what I've read the Sapphires should allow flashing the BIOS the same way, but it's a gamble whether or not you'll get lucky and unlock shaders..

I just used a circuit-writer pen to mod a second card:





Allowed me to flash the card with no problem again, but no unlocked shaders on this one either.

I'm not certain if I'm going to bother modding my other two cards, the heatsinks only came off these two so I could re-do the thermal paste.  

[edit]

fancy smartphone camera makes an amazing magnifying glass

This is also removable with a cotton swab and a bit of acetone.

Anyone else try this with the Sapphire 1gb 6950 without bios switch? I have two - and had the same error when I tried flashing in DOS. I don't want to risk bricking my cards again if it's impossible to unlock the shaders - even with an accepted flash.

Asher, do your successfully flashed cards now show the 1536 shader count?

I was thinking about trying this mod, but no one seems to have success with it yet besides you asher.  And you only got it to work on 2 out of 5 cards?  What kind of results did you get with it?

I'm glad to see people getting use out of the mod!

As an above posted mentioned, solid core wire is much better to use. I didn't happen to have any handy at the time. You can get it from ethernet cable (not all) or breadboard jumper cable. Those are the easiest places to find it.

That's because the worst binned 6970's become 6950's.
I.e. the last shader units are of very poor quality and are physically burned off from the GPU die with a laser.

Some 6950 GPUs are fully functional 6970's, artificially binned as 6950's to meet market demand.

Whether you get one of these units is just a pure luck of the draw. Just about all of the 2GB versions can be unlocked & AMD even included a BIOS switch for that purpose

GPUs in the 1GB versions are mostly the poorest yields at TSMC that are not fit to be full 1536 shader GPUs but not weak enough to be fully discarded/downgraded into 6870 GPUs with even more shaders cut off
if you do a hard mod by soldering & get lucky with a relatively good chip it might work, but with a much lower success rate than the 2GB ones

For you to see the full 1536 shaders, they need to be there physically, if not you will only see 1408 even after a successful flash

i just got a brand new powercolor 6950 1gb, good thing is that it's flashable with no hardware mod, but i couldn't unlock the shaders. oh well, it's 1gb version so i didn't really expect shaders to unlock. i just wanted it to be flashable without hardware mod, which it was

so after all i did manage to use this physical mod to flash my sapphire 1gb.
i used winflash and i said flash was ok!

unfortunately i still only see 1408 shaders instead of 1536

It's hit or miss whether or not the shaders will be available on any given card, even two cards in the same model/revision.

Nobody knows for certain how the shader cores are disabled on these cards, the people insisting 'laser cut' are talking out their ass or parroting someone else who was talking out their ass

When you see 'laser cut' you can assume this to simply mean 'disabled in hardware' until someone can confirm.

It's also possible the disabled shader cores are simply non-functional on many of these cards, bottom-binned so to speak.

i did this mod a few weeks ago on my 2gb Sapphire hd6950... it allowed me to flash with a modded bios
from my original bios (modded with rbe) but after a reboot the card still had only stock shaders (

most rubbish..... when people say they are "laser cut" are they referring to the gpu die its self ?!

Used the 'bubblegum' mod on one of my XFX 1GB 6590 ZDNC, worked like a charm but it's a big PITA to get placement right!

Instead of bubblegum, I used a chunk of window sealant putty and a bit of solid-core ethernet wire, works the same and you don't have to chew on it first

Shaders didn't unlock but the flash took with no problem at all.

I'm going to pick up one of these circuit-write pens instead for the other 3 cards: http://www.radioshack.com/product/index.jsp?productId=3964901

he can just put the wire and gum back and reflash

Wow asher, you've got some balls to do that to your card!  How did you figure out those pins needed to be shorted? How are you going to reverse it to take advantage of warranty without them being able to tell you did it?  Shaders unlock gives you about 40 more Mhash, but I don't know that it's worth voiding the warranty like that.  Kudos.

Not been able to make it work meaning what? If the flash wasn't work, then you're doing something wrong. If the flash works but the shaders aren't unlocked, then you are out of luck.

I found out that the Sapphires I tried to flash were unflashable.  I haven't tried the physical mod that asher2 posted, but that takes some guts.  I just settled for an overclock that netted about 350MH/s per card.

Has anyone else had success with this? I've tried two 1GB 6950's and not been able to make it work... (using the hardware mod detailed above)

Sapphire 6950's purchased last week

Well, that is false :p

I'm not saying all of them can, but many of them certainly can.

I agree. Use a modified version of the BIOS on your card, not the BIOS from another card.

i've heard 1GB versions can't be unlocked hmm

I think this poster is right on this one.Flashing a BIOS on hardware that's not made for it will have nothing buit problems anyway. The only feasible way I see is to export a BIOS copy with RBE,(and then make sure to have 2 copies,1 stock and 1 modded copy-with shaders unlock),then unlock shaders in that program then flash it back,the success rate is higher than flashing a different hardware's BIOS on though,as you're simply flashing the same hardware's BIO except with the extra shaders unlocked,therefore boosting performance and crunching power for mining BTC.

I hope this helps.

Yup.

I have a 6950 that can't flash... it says "cannot erase rom" when I try to flash it using winflash.  So this mod would fix that issue?

They fail differently depending on how I try to flash. With atiflash theres just an error message. When I tried winflash my PC locked up.

If you are flashing fine and the shaders are just not unlocked, then thats bad luck. If you are having an error with the flashing itself, then this trick will overcome it.

Very interesting guide, thanks for posting!

How do these cards fail when you try to flash them unmodded?

I have an HIS card that will not flash and I am wondering if I can use a similar trick to unlock it

Asher’s chewing gum 6950 mod.

What is this?

This is a hardware mod that allows you to flash your 6950 BIOS. 6950s can be thought of as coming in 3 flavours; those with a BIOS switch, those without a BIOS switch that allow flashing, and those without a BIOS switch that don’t allow flashing. This guide is for the last group. Always try just flashing first to see if it works. I STRONGLY recommend using atiflash for this, not winflash. This is because you may cause problems if you try with winflash and fail, but atiflash will generally just deny the flash and leave the card unchanged. This happened to me.

If you don’t know how to back up your BIOS and make a modified version, go find that out first!

So, whats the mod all about?

This mod is simply shorting some pins on an IC that allows you to flash your BIOS. This mod is temporary – you can remove it once you have successfully flashed your BIOS. I am going to go into detail for every step for those that are nervous about doing it. You can skip towards the end if you know what you’re doing.

What do I need?

Your 6950, a screwdriver, a small piece of wire, and some chewing gum.

Chewing Gum?

The credit for this mod goes to SlaveOnDope here. When I tried this mod, I had a lot of trouble looping the wire through the legs of the IC and stopping them touching the adjoining legs. Admittedly, it was in the wee hours of the morning and I was very tired. I came up with an easier method that gets the job done quickly and allows you to remove the mod easily even after you have replaced your cooler on your card.

Here is how it’s done...

This was done with a Sapphire series 6950. The procedure will be the same for all cards as far as I know.


http://img41.imageshack.us/img41/4293/dscn2656o.jpg
Here’s what the Sapphire card looks like, get a nice soft work surface to prevent damage.

http://img845.imageshack.us/img845/9822/dscn2657h.jpg
Unplug the fan.

http://img691.imageshack.us/img691/5749/dscn2658y.jpg
Flip the card over and remove the 4 cooler screws.

http://img39.imageshack.us/img39/4061/dscn2659mz.jpg
Separate the cooler from the GPU and locate the IC as indicated.

http://img811.imageshack.us/img811/3618/dscn2661j.jpg
These are the two pins that will be bridged across.

http://img18.imageshack.us/img18/9257/dscn2667a.jpg
Notice two things in this image. The first is that a tiny ball of chewing gum has been put on top of the IC – this is where the name ‘chewing gum mod’ comes from. Also notice that there is a small piece of wire below the card. This is about 1cm long with the plastic removed from each end and the ends bent at right angles. This is what we are going to use to bridge the legs of the IC.

http://img585.imageshack.us/img585/1033/dscn2654p.jpg
Stick the wire to the gum so that the bent ends touch the legs of the IC. It may take a tiny bit of fiddling to make sure the wire is in contact on both sides. I used tweezers as I was too clumsy with my hands.

http://img87.imageshack.us/img87/9081/dscn2676h.jpg
Put the cooler back on and flash your BIOS! Remember to plug the fan back in! You can see here that the mod is visible when the cooler is on. When you are done, just pull the mod off with tweezers or whatever without needing to remove the cooler again.

Good luck, have fun!

I have soldered a wire onto the BIOS chip to enable flashing and have flashed with a RBE modified BIOS. it has however made no difference to the performance of my sapphire 1G HD 6950 as I believe the extra shaders have been disabled when the chip was made.

The odds of getting a 1gb card that will unlock shaders when flashed is like winning the lottery. Even if you can flash it from modding it, it doesn't guarantee that you will be able to unlock the shaders. Most of the 1gb cards out there have the shaders laser cut (this is often referred to as hard locked) so they can't be unlocked no matter what you do.

now that would be very cool! thx in advance!

I'm going to write up a guide soon.

Can I ask what that was? I have a couple of these cards and was resigned to the fact that they would not be able to be flashed.

Theres a lot of nonsense being spoken about in the thread (not all of it is, of course)

I have 5 of these Sapphire 1GB 6950s

The first two I got flashed to the modded bios fine first time.

The next three I got were actually OLDER than the first two (by serial numbers) and they would not flash. I did a hard mod (no soldering required) and was able to successfully flash them.

Try just flashing first and see what happens.

I'll probably do a pictorial guide of the hard mod later.

GL.

In case it does not work you going to need to put another VGA card or a onboard video as primary in order to boot up and re-flash it.

The odds are against you in this one, i dont think it can unlock at all, you tryied to seach the product serial in google to see if someone has sucessfully able to unlock it?

If you're unlucky, you will permanently brick it (thats where the bios switch saves the day). But since it won't work, there's no point trying. Most of the time though, you will be able to reflash it.

ok thanks for the info!

let's say i would try it nonetheless. will my card get broken?
or will i always be able to reflash to the original bios?

well, the fa is in the midle, here no AMD logo on the pci-e  and you said there is no bios switch either.

The card dont have to be reference to unlock, but i think that Sapphires non-reference does not unlock.

thanks for the info! how can you tell it is a non-reference one?

No, what you need to do is to save to file you vga bios using gpu-z, then load it with RBE, go to the addicional tab and select 6970 shader count.

Save bios and flash the card, keep a backup and have another card on hand in case the card dont boot up and you need another one to re-flash it.

But you have a non-reference Sapphire one, i think those dont unlock at all. I have 2 XFX 6950 1GB ZNFC and those does unlock, and have bios switch.

Hmm, I have a no-switch XFX 6950 1GB that can't be reflashed with a shaders-unlocked BIOS.. d you think a soldered connection can make it flashable? Very interested in pointer if possible.

Hmm you will need to do some soldering to unlock that card
I have created an image with the info but can't upload a photo PM me and I'll send you it if you like

no i cant find a BIOS switch on it.
so this is the card:

Don't do eet! You'll brick your card! They are incompatible!
I suggest going to some hardware forum and asking first or finding some info before you do anything. check this post http://hardforum.com/showpost.php?p=1037084150&postcount=16.
You don't have a bios switch right?
Once you're confident enough that you know what you're doing, dump your bios, make about 15 backup copies, modify it with RBE, and pray that you can flash it back. Or, even better, see if you can find an already modded, working bios for YOUR SPECIFIC CARD on a forum.
good luck

If you want modding/overclocking options, ask on an overclocking forum (i.e. EOCF).

A 2GB card likely will have different memory timings, memory, size, etc. programmed into the bios that all could bork your card. Your 1GB card is not capable of running these settings at default.

why is that, several people have done it successfully.

flash it and u r guaranteed to brick your card.

Load the bios into RBE, unlock shaders and write back the bios.

Most of the newer cards are actually locked (either flash is protected, or they're fused). So good luck.

ok thanks a lot!
anything else i should do while i use RBE?

Do not flash 2gb bios, use RBE to read your card bios then unlock the shaders.

hello, i would like to flash my 6950 to a 9670 using the BIOS as many have done already.

the only thing is that i have a 1GB version and on this page only BIOSes for 2GB cards can be found:
http://www.techpowerup.com/vgabios/index.php?page=1&architecture=&manufacturer=&model=HD+6970&interface=&memSize=0

is it safe to also use this BIOS for the 1GB model?

thanks!