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Why do i say that?

Well for starters this thing will do 630 mhash/s and 680 khash/s (for scrypt).

that is absurd.. i have a sapphire 7970 that can barely do 680 and 720...

for balls to the wall all out mining this card is tough to beat.

it IS voltage locked however, which is a downside compared to the rev 1.0.

however, the rev 1.0 had no heatsink over the VRM's.. so those things were the limiting factor for the clock speed.. take it over 1150 for BTC mining and poof.. thermal shutdown.. the rev 2.0 does 1200 all day long no issue.

so.. just my thoughts. anyone else use this card?

I got your PM, thanks for the info.

But I have my Gigabytes at nearly the same spaces and they're only getting 570KH/s. I say nearly because even in single card config they overclock like crap.  These are rev 2.  They'll be going back to Frys. Probably will get some Sapphires since they seem to clock better.

Perhaps the batches at Frys are crappy.  Also I'm using Intel setups, so that may be part of it.

Yup, im liking my gigabyte 7950s.  600 kh/s at 1050/1450 clocks, the cards on risers never get above 70, the ones right on the board never get above 80.  They took a bit to hammer out the perfect settings and I could only get those speeds on cgminer 2.11.3 and up. 

Higher thread-concurrencies and intensities levels (18) made everything perfect.  I think whats interesting is how different they run from my 7970s.  I can't get the 7970s to run at 700kh/s at high thread-concurrency levels...im stuck in 2.10.5.  Moving up to 2.11.3 drops hash rate to 500 regardless of any settings.

In my case, there is always a trade off between hash rate and voltage.
I can't get both work in my favor, so I choose to undervolt all cards over hash rate :D

but gigabyte 7950 is always nice to have, with 3 fans the temp will be good.
maybe I will consider to change some of my reference cards with AC 3 aftermarket vga cooler (wait till the next BTC price shoot up :D)

What are your guys' settings for the rev. 2 Gigabyte 7950's that you are getting those clock speeds?  When I try to OC mine, either my computer crashes or my display driver crashes and it reverts to stock.

1.  What are you using to OC? 
2.  Do you have CCC installed at all or just the driver?
3.  What are your OC settings?
4.  What are your settings in reaper or CGMiner?

Power is the #1 issue with poor overclocks. Do you have a good PSU?

Let me just report working settings for me on a SAPPHIRE HD7950 3G GDDR5 (using Trixx)

GPU Clock 1190
Mem clock 1040
VDDC 1.206
Board Power +20

(Sidebar Gadget reports actualy 1.125V, 62W VDDC power, 55 Amp, 59 Celcius at 78% Fan)

This is ok for 24/7 in a 20 Celcius room and gives in bitminter around 610-615 Mhps
I can give another 10 or 20 Mhz but it becomes unstable.

PC works ok on everyday tasks.
For GPU intensive tasks (eg photoshop) I disabled the GPU hardware acceleration, so that it doesn't interfere with mining :)

I have both the Sapphire and the Gigabyte rv 2. 

I prefer the Gigabyte card. It does 620 k/hashes for me while my Sapphire's do 580 currently.

Both are really good though. And tbh I have not really tweaked the Sapphire's to a great extent yet, so maybe they'll get over 600 without too much trouble.

I also really like the cooler design of the Gigabyte card though, because the lack of plastic on the top of the card makes them perfectly open for a fan above them, which can blow air right down through the cooling fins of the entire card.

Are we talking about the Gigabyte Windforce 3?

Yes. I'm under the impression that the rev 2 is the currently available Windforce cooler card.. i.e this guy:

http://www.directcanada.com/products/?sku=11830BD3894

My apologies if that's not the card; that's the model I have anyways. I'm not a 100% on this.

It has a 8/6 pin power connector and is voltage locked unlike the earlier 6+6 pin unlocked ones.

bought a few dozen of the new sapphire 7950s when newegg introduced them a few weeks back. they were $289 with $20 amex gift card, and the 2 free game codes (i sold the majority of them for around $40-50), bringing the cost down to about $220. Excellent deal and honestly the best mining cards i've ever used.

+2.

7950's v2 best bang for your buck

Can someone link me to one of these Rev.2s please? Cant seem to find the difference on websites between the rev. 1 and 2.

I believe Gigabyte only makes one model of 7950s, the GV-R795WF3-3GD (http://www.newegg.com/Product/Product.aspx?Item=N82E16814125414). While it's technically voltage locked, a lot of people are switching to the F43 BIOS (http://www.gigabyte.us/products/product-page.aspx?pid=4121#bios), as it runs at a lower stock voltage, saving power and heat.

Thank you, I saw this one but it doesnt mention the rev2. Now this makes sense that its just a BIOS upgrade.

I have the same card and have trouble getting it over 600Mh/s


Could you provide your config please.
Or maybe you could post it in this thread (which is specifically for this card):
https://bitcointalk.org/index.php?topic=208514.0

Ditto. I'm running the Sapphires at 1185 core 300 mem. They do 610 Mh/s a piece at 59C with 75% fanspeed and 1.08V. Amazon has great deals on them too, plus ship exchanges 1-day with prepaid return shipping if you happen to need (fry) it. They'll also match their own prices with a refund if they go down (I just got about $65 back from them due to lowered prices on a rig I bought a few weeks ago).