GeCube does Dual GPU
In this case, GeCube managed to make dual GPU technology work by placing two GPU's onto a single PCB with two separate memory buses each holding 256MB of DDR-3 memory each and linked internally through a PLX bridge which supports a total of 32 switchable PCI-E lanes. All of this is achieved using a method that GeCube call "Self-Crossfire" - just adjust the driver a little to make it think that the single card with two GPU's is actually two separate cards. Before you get too excited though, currently there is no way to run Crossfire with a quad GPU setup. If ATI / AMD change their drivers to support quad GPU Crossfire, then in theory GeCube Gemini 2 cards should do Crossfire (quad GPU) but that's yet to be proven but an interesting thought to ponder.
GeCube assures us that they got it right this time - after working very closely with the ATI driver team, performance is solid to the point where they are claiming around a 65 - 75% performance improvement over a single GPU... and stable and not the size of the moon! Thermal issues are under control and they've managed to do it in a cooling package which only uses a single slot design. They even ran thermal tests in a test lab heat chamber which runs anywhere from 45 - 70c and no stability issues were noted.
They've developed their own DVI cable which allows for Quad DVI output using their DMS59 cables. While the card runs hot using the super reliable and accurate touch method (joking!), we never noticed any artifacting or crashing during our testing. For a graphics card which houses a couple GPU's, the cooling solution is incredibly quiet - we expected it to scream like a jet going for takeoff but they've managed to keep noise levels very respectable indeed by making use of loads of copper (it's heavy!). The mosfets are also cooled with passive cooling to aid in heat reduction. It manages to pack in 512MB of DDR-3 memory (256MB per GPU), solid capacitors for enhanced durability, upcoming physics support and a HDCP key for playing back HD video content.
As far as pricing goes, it should sell for around the $300 USD mark, give or take a few bucks and depending on your region. For comparison and based off street pricing, a single Radeon X1950PRO will cost you around $250 USD, a single Radeon X1650XT over $180 USD (since there is not much available) and a Radeon X1950XT 256MB version will cost about the same as GeCube's Gemini 2.
During testing of the cards we were interested to find out if you would still need an official Crossfire supported motherboard to run the Gemini 2. A little to our disappointment, we were told that you will need a Crossfire motherboard. Don't forget that the dual GPU technology is still operating under Crossfire mode and unless you modify the driver, Catalyst won't let you enable Crossfire mode if it detects a non-Crossfire supported motherboard.
We were able to run some benchmarking comparing the GeCube dual GPU card against a regular Radeon X1950PRO 256MB. Read on and check out the performance now you know about some of the details of the card!