Ahh, new generations of video cards. Gamers and overclockers eagerly await their arrival every time a new one comes around. This one was met with a bit of controversy when rumors circulated that AMD was changing the numbering scheme. That they did, but is the relatively inexpensive 6870 a stout contender – especially for the price? Let’s find out.
Barts – The New & Improved 40 nm GPU
The first of AMD’s Northern Islands graphics family to be released, Barts is the code name for the GPU contained in the 6800 series. While it’s not a process change (32 nm was apparently abandoned and 28 nm isn’t ready), it is a massive change in efficiency and capability.
Barts is AMD’s stab at taking the price-for-performance crown. Coming in at an MSRP of $239, the 6870 is quite an affordable option for the mainstream gaming / benchmarking market. The 6870 has fewer stream processors, fewer texture units, fewer transistors and ever so slightly reduced memory bandwidth as compared to the 5870 of last year. As we go through the benchmarks though, you’ll see just how much the architecture improvements have allowed it to compete with the older GPU.
As for the rest, we’ll let AMD do most of the talking.
One big focus are the updated tessellation unit. As you can see here, the improvement in that department over the previous flagship is impressive.
Everyone already knows AMD just loves to come in as the price-for-performance king. This has not changed since the acquisition of their graphics arm. Not only is that important, but with the launch of Barts, they are also focusing on more performance per… well, per everything – per square millimeter, per watt and per dollar.
Now we get to the matter at hand, the 6870 and its specifications.
The AMD 6870 -yes, that’s right, ATI is no more- is a rather good looking card as stock reference cards go. It’s got a bit more flare than previous generations, which is a welcome change.
Changing angles a little bit we can see the card’s connectivity. There are five monitor connections on this card, including two DVI, two mini DisplayPort and one HDMI.
That’s quite a lot of multi-monitor capability right out of the box. It’s a solid improvement over the previous generation with any number of ways to get yourself up and running with eyefinity.
Here we see the power connectors, for which two 6-pin PCIe cables are required – another pleasant note for those that have smaller power supplies. No 8-pin connector means it’s not a power guzzling monster.
The 6870’s cooler looks nice on the outside, but what does it have underneath?
It seems the cooler consists of a copper base with three heatpipes connected to aluminum fins for heat dispersion. The fan is your typical squirrel-cage-style fan that also serves as the air intake. As you can see exhaust is ducted to go around the two DVI ports and out the rear of the card.
While the memory and MOSFET contact points look plastic, they are metal and seem to cool their components effectively.
In use, the fan is reasonably quiet up to 50%’ish speed. At 60-65% it’s definitely noticeable. Much past that and you’ll either want to use headphones or be using the card for benchmarking as It gets quite loud.
|Card:||ASUS Matrix 5870 Plat.||AMD 6870|
|GPU idle – Stock & OC’ed||39° C||34° C|
|GPU load – Stock||66° C||59° C|
|GPU load – Overclocked||71° C||70° C|
With the stock fan @ 65%, temperatures were actually better than those of the Matrix 5870 Platinum, with its superior cooler and its fan operating at 75%. This is a nice, cool running card (we’re looking at you NVIDIA).
6870 – Defrocked
The card itself had a very liberal amount of TIM on the GPU with thermal pads for the memory and MOSFETs. Unless you plan on volt-modding the memory, these thermal pads will prove sufficient. I replaced the MOSFET thermal pad with some ceramique since some voltage increase was planned.
It would have taken a lot to get every bit of the TIM off of the socket area, so I just cleaned the GPU itself and as much as I could manage of the surrounding area without going crazy. digging too deep into the small electronics surrounding the GPU. A little TIM isn’t going to hurt them anyway.
The 6870 comes with a TDP of 19 W idle and 151 W under load. Putting the test system on a kill-a-watt (tested to be accurate +/- 2%), it fares pretty well against last year’s 5870.
|Power State||AMD 6870||Matrix 5870 Platinum||4890 Turbo|
|Idle||166 W||208 W||235 W|
|GPU Loaded||316 W||398 W||364W|
With each generation, they get better and better. Granted, the 6870 isn’t going to be the top 6xxx card for long (and we’re curious how the 69xx will fare power-wise), but it’s still a very marked improvement over the 5870.
Overclocking this card was a pleasant experience after figuring out what software to use. Sapphire’s new software TRIXX worked quite well. A beta version of MSI Afterburner floating around worked but no more effectively than Catalyst Control Center because it would not allow voltage adjustment. Once I was pointed in the TRIXX direction all was well. Big thanks to forum senior member and benching team leader Brolloks for that little tidbit.
The maximum stable overclock I could get at stock voltage was 943 Mhz on the core. It passed several benchmarks at that speed. Memory was slightly shaky at 1200 MHz and was reduced for overclocked runs to 1175 MHz.
TRIXX allowed voltage adjustment up to 1.3 V (well, 1.299 V). This brought the core to a solid overclock of 1035 MHz on the core. As mentioned previously, the memory was reduced to 1175 MHz to ensure stability out of it. These two screenshots were 3DMark Vantage because the card would pass Furmark further than it would pass Vantage; go figure.
1035 passed all benchmarks, but not all game tests. Tessellation really beats on an overclock apparently. For most game tests 1030 MHz was fine; but for the Heaven benchmark – which is very strenuous with tessellation set to Extreme – it had to be dropped to 1025 MHz.
Overall not bad clocking on a card that’s clocked pretty high to start with. There is a very marked improvement in all scores and games, as you will soon see. With 1.5 V applied to the core, I’ve seen some reaching 1,200 MHz and above.
Test System & Methodology
This test system should be familiar to anyone who read our previous review of the ASUS Matrix 5870 Platinum.
|Processor||Intel i7 870 @ 4.0 GHz|
|Motherboard||EVGA P55 FTW|
vs. Galaxy GTX 470
vs. ASUS Matrix 5870 Platinum
vs. Gigabyte 5870 SOC
vs. HIS 4890 Turbo
|Power Supply||Cooler Master Silent Pro Gold 800W|
|Operating Systems||Windows 7 x64 / Windows Vista x86|
Stock benchmarks were run three times and the average is reflected in the graphs below. Overclocked benchmarks were run once. Please note in the graphs below, they do not begin at zero so the differences in score can be highlighted. The actual performance difference can amount to as little as a couple dozen points or a couple FPS, so pay attention to the numbers inside the graphs as well.
The Gigabyte and HIS cards were not included in gaming tests as they are no longer available to test. The Galaxy GTX470 tested in this review was very generously loaned to us by forum senior member and regular Overclockers.com writer EarthDog, which we are very grateful for! Speaking of the GTX 470, you should know that all overclocked runs were completed with a 750 MHz GPU clock, a 875 MHz memory clock and a 1500 MHz shader clock.
Performance, Stock & Overclocked
Many overclockers start coming here for one reason, and one reason only – getting more FPS so they can kill more enemies! It’s most definitely why I started on the overclocking journey. Thankfully, overclocking can help you do just that.
We’ll use three games to test the 6870’s FPS acumen – Stalker: Call of Pripyat Benchmark, Aliens vs. Predator DirectX 11 Benchmark and Heaven Benchmark. All were run at 1920 x 1080. For overclocked runs, Stalker and Aliens vs Predator were both run with 1030 MHz on the GPU, but Heaven had to be dropped to 1025 MHz. The memory stayed constant at 1175 MHz.
Stalker: Call of Pripyat
There are three graphs showing various settings that were manipulated. All results reflect the average of the four average FPS readings in the different stages of the benchmark. Common settings include the Ultra preset using the Enhanced full dynamic lighting (DX11) engine with a resolution of 1920 x 1080.
The games were first run with no MSAA and no tessellation. Then MSAA was cranked to 4x and tessellation was still disabled. Finally, they were run with 4x MSAA and tessellation enabled.
The GTX 470 sure struts its stuff in this bench. However, for a card designed -and priced- to compete in the $240 segment, the 6870 has a very strong showing against the previous generation’s top dog. It also shows off one of the 6870’s new strengths – improved tessellation. You can see that it clawed back a few FPS in the runs with that enabled.
Aliens vs. Predator DirectX 11 Benchmark
AvP was run in two modes – one with the default configuration and the other with everything cranked as high as they could go. The differences between the two are Texture Quality (changed from High to Very High) and MSAA (changed from off to 4x).
With the default settings in AvP, tessellation is turned on. As you can see, the overclocked 6870 is right up there with the overclocked 470 and the stock 6870 is actually beating the 470. The computing workhorse with everything turned up is clearly the 470.
Regrettably, I didn’t run the Heaven benchmark at its default settings. Hindsight being 20/20, that was a less than intelligent move on my part. Since the 470 is back with the individual that so generously let us borrow it for this review, it is what it is; live and learn.
Only two items were changed from the default setting – Tessellation was increased to “Extreme” and Anti-Aliasing was changed to 4x. All other settings remained the same.
The 470 definitely shows off some strength in this grueling benchmark (kudos for HWBot for making such a crazy difficult bench!). The results would likely be more disparate if tessellation were turned down. The 6870 did show a surprise by giving the 5870 a solid beat down.
Mmm, benchmarks. These are the results benchers are looking for. Getting right to it, we’ll start with the oldest of the 3DMarks and the tweakers’ dream 3DMark01. Note that all 6870 overclocked benchmarks were run at 1035 MHz on the GPU and 1175 MHz on the memory.
Why hello 6870, what’s that? You perform great at 3DMark01? So it would seem. The only card that beat it out here is the Gigabyte 5870 SOC, which was the highest-clocked 5870 on the market.
This one loves to torture some overclocks, but it didn’t force any reduction here. 1035 /1175 continued to be stable.
The 5870 Platinum fell to the 6870, but the 470 and especially the 5870 SOC came out ahead in 03. Still, it continues to be a strong performer.
05 is more of a CPU-bound benchmark, so differences when overclocking aren’t as marked as some others.
That said, it’s still impressive to see the 6870 taking out both 5870s and only losing to the 470.
With 06, the CPU comes into play a bit more with a weighted score from both the CPU and the GPU contributing to the overall score.
Everybody is right there in a heated battle. The 5870 Platinum (with its 2 GB of memory) and the 470 (which has 1.5 GB of memory) come out on top in 06.
Last, but not least is the current top-o’-the-heap for Futuremark. They’ll have a new flagship soon in 3DMark 11, but until then, this is as rigorous as it gets.
This one is a not-so-bright spot for the 6870, only beating the 4890. On the plus side, overclocked it is within 1000 points of the 5870 Platinum and beats the stock 470. Still a pretty good showing for a budget card.
Last, but not least we have my personal favorite 3D bench. This is mostly a CPU benchmark, but does benefit from a speedy GPU.
Well then; the 6870 sure showed off here, beating all of the competition at stock and simply increasing its lead overclocked. Good show!
Some of you may have read our recent review of the Crosshair IV Extreme. While seeing how far I could push a Phenom II x6 1090T, I ran a couple 3DMark06 and 3DMark Vantage tests to see how the 6870 would fare with a strongly clocked hex-core behind it.
With the main focus on Vantage, 06’s results stopped short of the max frequency. Still, with a Thuban at 5142 MHz giving it a nice boost and the 6870 at 1040 / 1180, it gained very close to 3,000 points.
The 1090T gave up a few extra MHz in Vantage before it was all over. Running at 5187 MHz with the card at 1045 / 1175, it gained almost 400 hard earned points.
While the Vantage result still couldn’t beat the overclocked 470, the 3DMark06 result beat it handily with a sub-zero CPU behind the 6870.
Final Thoughts & Conclusion
AMD has a winner here in my eyes. Entering the market with a brand new product at an affordable price? Check. Strong ability to overclock straight from the reference design? Check.
Unfortunately, what AMD didn’t seem to foresee was NVIDIA dropping the bottom out of its prices when it launched these cards. You see, AMD targeted the GTX 460 with this card. Prior to the 6870 launch, the GTX 460 was close to the $240 entry price point. As you can see here at Anandtech, the stock 6870 definitely beats the stock 460. I wouldn’t doubt the overclocked 6870 could beat an overclocked 460. What’s that they say about the best laid plans?
That’s why we brought you this comparison. The GTX 470 is now the closest NVIDIA card price-wise to the 6870, though it is still slightly north with an MSRP of $260 vs the 6870’s $240. I can’t imagine NVIDIA is necessarily pleased about selling its GF104 at that price point and whether they will stay there remains to be seen. If they do, there is a legitimate argument to be made for the GTX 470 from the results above.
The 6870 has an ace in the hole though – crossfire scaling. These cards do a superb job when you put them in crossfire. Brolloks, (Overclockers’ benching team leader), did some testing and while his 6870 didn’t beat his 5870 in a single-card 3DMark06 run, dual 6870s actually beat out dual 5870s quite handily. Take a quick look at the results from this Benchmark Reviews article. Two 6870s in crossfire consistently almost double their FPS / score. I can’t remember the last card (if any) that I’ve seen scale so well. If you plan on running multiple cards from this price point, there is a pair of 6870s with your name on them.
There is also heat and power to consider. Everyone knows Fermi is one hot beast. Running this GTX 470 through 3DMark Vantage at stock gave temperatures equal to that of the 6870 overclocked running Furmark. Add to that the GTX 470’s TDP – 33W idle / 215 W load and you have a power hungry, hot beast.
These are no small matters. AMD has managed to make a card for $20 cheaper that runs cooler, uses less power and performs pretty darn close to its competition. A lot of users would think those strengths outweigh the sometimes rather small FPS / score advantages you get for using so much more power and producing so much more heat.
So the 6870 runs cooler and sips quite a bit less power than its competition. Add to all of that the fact that these cards seem to be pretty darn good overclockers and you have a winning combination!
-Jeremy Vaughan (hokiealumnus)