AMD Radeon HD 7870 GHz Edition & Radeon HD 7850 Review: Rounding Out Southern Islands
by Ryan Smith on March 5, 2012 12:01 AM ESTTheoretical Performance
Before moving on from compute performance, we wanted to quickly take a look at theoretical performance. This will be particularly helpful for highlighting the importance of core clockspeeds in AMD's GCN architecture.
We’ll start with a quick look at tessellation performance with the DX11 Detail Tessellation sample program. Because the 7900 series and the 7800 series share a common dual geometry engine frontend, geometry performance is almost entirely dictated by the core clock. As a result the 7870 and its 1GHz core clock just edges out the 7950 and its 800MHz core clock when it comes to tessellation performance. The rest of the difference comes down to shaders, where the 7950 has more shader resources to throw at the hull and domain shading parts of the tessellation process.
Of course that tessellation performance lead doesn’t always translate into great performance in tessellation heavy benchmarks. Unigine Heaven, in spite of its heavy use of tessellation still has the 7950 well ahead.
Finally, a quick look at 3DMark Vantage theoretical performance largely confirms what we’ve already seen. Pixel fill is heavily bandwidth limited, leading to the 7950 taking a large lead and even the 6970 edging out the 7800 series, though you’d never know it from the gaming benchmarks. Otherwise when it comes to texture fillrate, the 6970 and 7870 are in a dead heat.
Facebook
Twitter
RSS
173 Comments
View All Comments
medi01 - Monday, March 5, 2012 - link
AMD released cards that are better than competitors in all areas: pricing, power consumption, performance, yet he found a way to be "dissapointed"You can't reason with fanboi.
Kiste - Monday, March 5, 2012 - link
You're the one who seems obsessed with which company releases the "better cards".I'm merely commenting on the 78xx line of cards, which I find underwhelming in terms of price/performance ration - and I am not alone wiht this if you bothered reading the other comments here.
So who's the fanboy?
formulav8 - Monday, March 5, 2012 - link
You are. Your annoying as well.chizow - Monday, March 5, 2012 - link
Try laying off the personal attacks and focus on the arguments instead.I don't see how anyone can defend the pricing of AMD's 7 series stack in good conscience though, if roles were reversed and Nvidia were the one doing this, EVERYONE would be disappointed too I'm sure.
Kaboose - Monday, March 5, 2012 - link
wasn't it everyone who said the 6000 series was too expensive back in october of 2010 and when Nvidia released the 500 series prices would come down a lot, then Nvidia released the 500 series right in between what AMD had and neither company really lowered prices for months. I think we will keep seeing more of that when the 600 series is released. This way BOTH companies profit.chizow - Monday, March 5, 2012 - link
Not sure what you're referring to, Nvidia launched GTX 570/580 before AMD launched the 6-series.And no Nvidia didn't raise prices on their 470/480 at the time which were at the same price points even though the 500 series extended that lead.
AMD priced the 6000 series accordingly, and I don't recall anyone complaining other than being disappointed it didn't offer more performance.
SlyNine - Monday, March 5, 2012 - link
5870 user here. What everyone defending the 7xxx node change doesn't consider that most of us dissopointed in SI are compairing it to other fab shrinks.Iketh - Monday, March 5, 2012 - link
You're on nvidia's payroll. Get off this site.sseemaku - Monday, March 5, 2012 - link
Are engineers in nvidia thinking in the same way and not releasing their cards! Good for AMD.medi01 - Monday, March 5, 2012 - link
7850 outperforms 570 while costing 80$ less.nFanboi much?