6950 laser cut shader unlock

myztikrice

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When people say newer 6950 cards are laser cut and can no longer unlock, do they mean no longer unlock with a 6970 bio or no longer unlock with a modified 6950 bios?
 

Dogsnake

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The bios change to give access to the additional shaders requires that the shader pathways are "hooked up" or physically and electrically connected. When it is said laser cut it just means that the gpu die has been modified by a laser to cut these connections and render them inoperable. Since what is being done is on a microscopic scale you need a laser to do it.
 

bystander

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I said no such thing. I said that the laser cut shaders are not unlockable, as the shaders are severed in the chip. There is nothing you can do to change those.

The guide you posted was for those with all the shaders intact but with a bios lock. The guide instructs you on how to remove that lock.

This is at the beginning of the guide you posted: 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.
 

bystander

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Here is a guide I posted a while back on how to unlock the shaders for all 6950's that are unlockable: http://www.tomshardware.com/forum/316974-33-radeon-6950-shader-unlock-instructions#t2368661

Unfortunately, since I posted this guide, there have been a few new techniques to stop this practice from the manufacturers.

One such method are those with a bios that is locked. Here is the first post I found on the subject: http://forums.extremeoverclocking.com/showthread.php?s=756ec20686b0df529e4b85862affebf7&t=355592
I believe on page two of that post there was someone who got around the locked bios, unfortunately that does not make all the cards unlockable.

The laser-cut shaders are something that is talked about, and was warned about by manufacturers, but I do not know if it's 100% a case of having laser-cut shaders, or just that more chips are coming out with defective shaders. These cards, whether defective or laser-cut, cannot be unlocked with any known method. If they are in fact laser-cut, it's not possible to reverse the process and unlock the shaders. Same goes for defective shaders.
 

Dogsnake

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I unlocked my 6950 shaders on a non reference single bios card. Just to clarify a few things. An unlocked 6950 is not a 6970. There are other differences besides the shaders. What you end up with is an improved 6950 (by 10%-15%). The safest method (least chance to brick the card) is to use the card's bios, unlock the shaders and flash it back in. Some people do flash with already unlocked bios that you can find on the web. Some duel bios cards had unlocked bios already installed. If the card is a non reference card (factory OC'd or with non standard cooling) it is best to use the first method because using a different bios may disable features that are factory set in the bios.
 

myztikrice

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I wonder if 'cards without a bios switch that don't allow flashing' are because of laser cut shaders or something else. Would else could block a flash? And is flashing a modified 6950 bios different than flashing a 6970 bios? Does either one have different success rates? How would a card have a locked bios without being laser cut?
 

Dogsnake

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Just to add to the mix, the cards that have been modded most successfully are the 2gig. versions. Myztikrice a card can be prevented from being modified by altering the gpu itself ("laser cut is one way), changing the connections on the printed circuit board, and in the bios chip by adding instructions that make the bios the one and only the card will accept. More cards have been bricked by using a 6970 bios than by using a 6950 bios. As I said before they are different cards and unlocking the shaders does not make a 6950 a 6970. There have been loads of people who tried to flash the bios and did everything correctly and the card bricked. My suggestion to you given your questions and constant wondering is that if you want a 6970 buy it. You seem to me to be one of those people who will end up bricked and very unhappy.
 

myztikrice

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I bought a powercolor 6950 and unlocked it just fine. I was contemplating the sapphire 6950 for a better stock cooler but was getting reports it was un-unlockeable. I wanted to know if it was true or if people are just dumb.