Club3D Radeon HD 6870 X2 Review - Two Barts XT go against the big boys

[siopao1984]

---

What happens when you slap two mid-range Barts XT (Radeon 6870) GPUs on a single board? Not too shabby at all...

Netherlands based Club3D products are mainly distributed and sold in Europe and Indonesia - so our predominently American and Singapore readers won't find them on local shelves.The 12 inch (30.48cm) long Radeon HD 6870 X2. Its cooling solution, dubbed "CoolStream", uses 6 heatpipes and 2 silent fans to dissipate heatNeeds 2 x 8 pin PCIe power connectors2 Mini-DP, a DVI-D and DVI-I and a single HDMI port.Accessories and Documentation. The card also comes with a free copy of the DiRT3 racing game

[siopao1984]

Heatsink removed - the 6870 X2 uses two 40nm Northern Islands VLIW5 based Barts XT (6870) and is clocked at 900MHz at stock.



A Lucid LT22102 PCIe bridge chip (48 lanes Gen 2) is used for onboard Crossfire communication between the two GPUs



16 x ELPIDA 128MB GDDR5 clocked at 1050MHz by default



For voltage regulation, the 6870 X2 is equipped a pair of CHiL CHL8214 (4+1 phase) PWMs, which supports voltage control/monitoring by I2C bus



CoolStream Cooling System



Actually made of 2 separate heatpipe blocks. Fans are made by Everflow (75mm T128010SU 0.35A@12v and 83mm T129215SU 0.5A@12v)

[siopao1984]

Overclocking





The Club3D Radeon HD 6870 X2 is clocked at 900MHz on the core and 1050Mhz on the memory by default. Voltage control was also available with MSI Afterburner. Unfortunately much like the behaviour of the original single HD6870, we could barely get a 10MHz increase on the core at stock voltage (1.175v) and temperatures were too hot (>100 degrees) causing thermal throttling when we increased the voltage. We could not get anything tangible out of the memory either.



Test Setup



CPU: Intel Core i7-3960X @ 4679MHz 1.48v
Motherboard: ASUS Rampage IV Extreme (latest 1004 bios with CPU Microcode/PCIe 3.0 fixes)
Memory: G.Skills RipJawsX 2133Mhz DDR3 16GB Kit
Power Supply: Cooler Master Silent M Pro 1000W
Storage: Intel 520 series 250GB SSD

Graphics Cards / Drivers:
Club3D Radeon HD 6870 X2 (Catalyst 11.12 WHQL)
AMD Reference Radeon HD 7970 3GB (Catalyst 11.12 Dec 20 Build)
ASUS Radeon HD 6970 DirectCU II 2GB (Catalyst 11.12 WHQL)
AMD Reference Radeon HD 6990 4GB (Catalyst 11.12 WHQL)
MSI N580GTX Lightning Xtreme Edition 3GB (Nvidia 290.36)

[siopao1984]

Benchmarks



SURPRISE! 2 mid range Barts XT combine to beat the mighty Radeon HD 7970 at stock, and manages to annihilate the HD6970/GTX580 in the process



Same story here too in the 1080p Xtreme Preset. Too bad it couldn't overclock...



This card is proving its mantle in the CrossFire friendly BF3 as well



Same performance lead in Unigine Heaven



In the AvP DX11 benchmark, it even manages to overtake the overclocked HD 7970, which is an amazing feat



This is where reality hits - Batman Arkham City and other games (COD:MW3, Skyrim, Red Orchestra 2...) which are not so Crossfire friendly will show poor or no or even negative scaling. Multi-GPU cards by nature are at the mercy of game developers and driver teams.



Not too shabby here, but a far cry from the new HD 7970

[siopao1984]

Conclusion



There is a lot that we like about this card. Priced at €379,61 / USD$496 / SGD$641, it comes in cheaper than the Nvidia GTX 580 3GB, which it beats in most tests by a considerable margin, even threatening the new single GPU king of the hill HD7970 on numerous occasions. What disappointed us was the lack of overclocking headroom - in part due to the inherent lackadaisical ability of the Barts XT to clock much higher and the suspect heat dissipation of the cooling system (uneven fan sizes?). Some may argue that getting two separate HD6870 cards will cost 15% less, but we should remember that the 6870 X2 puts two GPUs on a single PCB, eliminating the possiblities of motherboard compatibility issues and lack of card spacing causing thermal hotzones.

The real achilles heel of the card is the Crossfire scaling - which in this age of shoddy console ports and non-existant hardware compatibility testing, might take some time for Crossfire profiles to be developed after new game title launches, to enable proper performance scaling and fix visual anomalies/tearing. This might be a problem for indie/small-time game developers or engines, as they might not get enough attention from the AMD driver team.


Pros
HD 7970 levels of Performance
Relatively cheap compared to the GTX 580 3GB, which it beats most of the time
Many display outputs

Cons
No Overclocking Ability
12-inch length might be a problem in some enclosures
Dependent on AMD Crossfire driver support to shine

[Lingaw-lingaw_sa_payag]

kita man ku ani sa G.I APM oo..

[akomao]

kana unta imong ge palit boss HAHA

[kenox]

kita man ku ani sa G.I APM oo..

pila boss? sah apm?

[Archfear]

17K @ G.I. Tabunok Sapphire pa jud! wahehehe...

[kenox]

mas barato sah 580? nya mas kusgan? nindot ni dah...

ang naka bati lang...dli attractive ang card =))