Question about 6950 crossfire

[vaal420]

Heyas. I have one of the first 6950 2gb cards that came out. It's one of the ones that was shader unlockable to a 6970. I want to buy a 2nd 6950, but I worry that it will not be unlockable. So my question is, is my older 6950, that I have not unlocked going to crossfire with the 2nd gen non unlockable without issue? Also I dont think I will be able to get the same brand 6950 I initially purchased. Will brand make a difference, if the 2 cards are the same reference speed? Thanks in advance. I dont want to waste my money.

 

[3DVagabond]

Any 6950/6970 crossfire combination works. Just make sure you get a 2Gb card so you get full use of the RAM in your 1st card.

If you can get a 6950 Sapphire Toxic, most of them are also unlockable and in fact come factory unlocked.

 

[HendrixFan]

I am in the same situation as you. I was planning on picking up a 6970 on firesale when the 7000 series rolls out to run in crossfire, or if the deals weren't as good as I hope then I would go with the 6950 Sapphire Toxic.

 

[tenoc]

I have an XFX 6950 reference dual-bios and a newer one in CF.

From playing around with the older one I found there is little benefit to unlocking the shaders - maybe 1%, if that. Using a 6970 bios offers a good chance of frying the memory chips since the 6950 uses different (slower) ones than the 6970. YMMV!

A single stock 6950 benches about 10% off a stock 6970, and in CF the difference drops to about 5%!

Recommend leaving the shaders as is. Use TRIXX (free DL from Sapphire) to OC the GPU speed from 800 to whatever, leave the memory as is since the chips are already at their rated maximum (5000/4=1250). Yes, some will go higher but why bother?

Mine both happen to be XFX ($30 MIR on each of them plus double life-time warranty) but different brands will work just fine in CF.

To sum up, I've about $490 invested in 2 6950s versus whatever ($700?) 2 6970s would cost for only a 5% penalty in performance.

 

[Wuzup101]

I have an XFX 6950 reference dual-bios and a newer one in CF.

From playing around with the older one I found there is little benefit to unlocking the shaders - maybe 1%, if that. Using a 6970 bios offers a good chance of frying the memory chips since the 6950 uses different (slower) ones than the 6970. YMMV!

A single stock 6950 benches about 10% off a stock 6970, and in CF the difference drops to about 5%!

Recommend leaving the shaders as is. Use TRIXX (free DL from Sapphire) to OC the GPU speed from 800 to whatever, leave the memory as is since the chips are already at their rated maximum (5000/4=1250). Yes, some will go higher but why bother?

Mine both happen to be XFX ($30 MIR on each of them plus double life-time warranty) but different brands will work just fine in CF.

To sum up, I've about $490 invested in 2 6950s versus whatever ($700?) 2 6970s would cost for only a 5% penalty in performance.

Pretty much the same deal here. My cards are both unlocked (because I can't leave well enough alone). That being said, I wouldn't pay extra for a version that was factory "unlocked" or able to be "unlocked" at this point. When I purchased my XFX cards, all of the cards had a bios swtich and were unlockable. You get much more from overclocking that you get from unlocking. If the price was the same, than sure get the version with the bios switch (or factory unlocked shaders)... but don't pay a lot more for it.

My memory and core seemed to have plenty of overclocking headroom without having to use 6970 bios (for extra juice to the memory) or having to bump the core voltage too high with afterburner.

Also note... I have about the same $480-500 into my cards. I think I paid $269 or 279x2 and got the $30x2 rebates. For the price, they certainly were worth it (to me).

 

[vaal420]

Thanks for the replies! This is why I love anandtech =)

I would like to buy a toxic, but I cannot seem to find a 6950 Toxic anywhere. I couldn't find one even at newegg. Its like the card doesnt exist. Ill just get a normal sapphire 6950. Always have had the best luck with them.

 

[3DVagabond]

Thanks for the replies! This is why I love anandtech =)

I would like to buy a toxic, but I cannot seem to find a 6950 Toxic anywhere. I couldn't find one even at newegg. Its like the card doesnt exist. Ill just get a normal sapphire 6950. Always have had the best luck with them.

Sapphires are hard to find right now on Newegg. The Dirt 3 edition is the only model in stock. It has a custom cooler and dual bios. Always the chance you can unlock it yourself.

http://www.newegg.com/Product/Produc...82E16814102945