ASUS Radeon HD 7970 CrossFire

[theJesus]

it probably doesn't, but trackr would complain about it anyway

Yeah, I remembered wrong. I went back and checked your graphs and there wasn't much difference. I think there was a very slight difference, maybe like 1fps or something, but I forget already. Makes me wonder if the 7970 might actually be enough to make a more noticeable difference.

 

[buggalugs]

AMD has a 7970 driver on their website. Still no 12.1 WHQL though.....wtf are they doing??

The cards started at $699 in Australia and they still sold out, theres only a couple of models left so they bumped the price to $749, one store even had $800 on a 7970 and they still sold out.

They are basically charging anything they want and stock is disappearing fast.

Newegg has sold out too.

 

[Trackr]

it probably doesn't, but trackr would complain about it anyway

Why would I complain that more PCIe lanes don't make a difference?

That is my argument.

You're the one who said that it WOULD make a difference to have two cards in two PCIe 2.0 x16 slots as opposed to two PCIe 2.0 x8 slots.

 

[blibba]

Why would I complain that more PCIe lanes don't make a difference?

That is my argument.

You're the one who said that it WOULD make a difference to have two cards in two PCIe 2.0 x16 slots as opposed to two PCIe 2.0 x8 slots.

Wizz was saying that you'd complain that they do make a difference, if he used a P67 or Z68 platform for the test.

As it happens he used an X58 platform, so you complain about it being too slow (even though its plenty fast enough that when you hit its CPU bottleneck, you're talking about silly FPS anyway).

His remaining alternatives are X79, which still has some issues with CF as I understand it, and Bulldozer/Phenom II. Yeah...

 

[XacTactX]

7970 CrossFire uses less power at idle than an HD 5770 (13w vs. 15w). Someone tell me that's hilarious.

 

[FreedomEclipse]

7970 CrossFire uses less power at idle than an HD 5770 (13w vs. 15w). Someone tell me that's hilarious.

not really... thats just the 7970's 'ZeroCore power state' at work. IT can completely shutdown a GPU if it isnt in use

 

[Trackr]

Wizz was saying that you'd complain that they do make a difference, if he used a P67 or Z68 platform for the test.

As it happens he used an X58 platform, so you complain about it being too slow (even though its plenty fast enough that when you hit its CPU bottleneck, you're talking about silly FPS anyway).

His remaining alternatives are X79, which still has some issues with CF as I understand it, and Bulldozer/Phenom II. Yeah...

So, he was suggesting that I would complain about PCIe 2.0 x8 bandwidth because I complained about i7-920 performance?

But those are complete opposites.. PCIe 2.0 x8 does not bottleneck performance. i7-920 DOES bottleneck performance.

It seems like he was just trying to insult me instead of listen to my comment..

 

[blibba]

So, he was suggesting that I would complain about PCIe 2.0 x8 bandwidth because I complained about i7-920 performance?

But those are complete opposites.. PCIe 2.0 x8 does not bottleneck performance. i7-920 DOES bottleneck performance.

It seems like he was just trying to insult me instead of listen to my comment..

He was taking the piss out of you for complaining about things that aren't really problems.

He succeeded. And, to make it even better, you didn't get it.

 

[treehouse]

So....according to the summary... adding another 7970 for crossfire only gives it a 24% boost over the single card??

that makes it real hard to justify getting 2 cards.

cpu limitation

 

[XacTactX]

not really... thats just the 7970's 'ZeroCore power state' at work. IT can completely shutdown a GPU if it isnt in use

So what part of my statement needed correcting? ZeroCore or not it still uses less power... which is awesome!

 

[Darkleoco]

Nice review, shame we can't have decent Crossfire Drivers yet, hopefully the aftermarket versions will be released after proper drivers

 

[Trackr]

He was taking the piss out of you for complaining about things that aren't really problems.

He succeeded. And, to make it even better, you didn't get it.

He only succeeded because he said something so vague that I thought it made it sense, when it actually made no sense at all.

And he did that INSTEAD of listening to my concern.

Believe what you want, but running a 4.0Ghz i7-920 IS a problem.

How can you think that a 10-20% CPU bottleneck in a high-end review is not a problem?

I'm astounded.

 

[Fatal]

Great review Wizz but the cards are too much for my broke ass right now

 

[blibba]

How can you think that a 10-20% CPU bottleneck in a high-end review is not a problem?

This sentence shows how little you understand. It really pisses me off when people spend the kind of money that you have without doing any research into these things.

CPU bottlenecks are at a fixed number of FPS for any given set of graphical settings, drivers, OS etc. They are not a percentage penalty. If you get a Sempron and couple it with two 7970s, and then with four, you're going to get identical FPS in every game. According to your implied theory, you should get a discounted version of the FPS you'd get on a high-end platform.

Wizz's graphs only show averages. So you're getting the average of the times when the GPU was able to open up, and the times when the CPU was limiting every graphics solution to roughly the same FPS. This can look like this:

But as you increase the resolution, the FPS spends less and less time being capped by the CPU and more and more time being capped by the GPU, so you get results like this:

As an overclocked i7-920 never imposes a bottleneck at anything even near unplayable FPS in any games in the suite, I really don't see the issue. The graphs show that at 1024*768 or in undemanding games, there's a tiny difference between one 7970 and two. Yes, they'd show a bigger difference with a more powerful CPU, but who cares? The graphs also show that the i7 920 is almost never a bottleneck at 2560*1600 - note near perfect scaling in crossfire in many games. And that's what anyone reading this review is likely to actually care about.

 

[fullinfusion]

Nice review Wiz
but $1100 for 2 of these cards? Not in this life time. I think I'll hold off on this round and grab a 6950 to add to my system and have better performance then two of these suckers and still be cheaper

 

[Avelict]

So I'm in the process of acquiring a new rig for gaming and high poly count 3-d rendering using mainly Maya/Zbrush. Im pretty set on the CF7970's, and Im planning on the i7-2600k with OC set to 1.4vcore. At that speeds do I still need to worry at all about the CPU bottlenecking my system at all?