Chillblast Fusion Venom

Chillblast has graced the pages of PC Pro with several innovative systems recently: one of these - the Fusion Trident - employed triple-SLI but didn't offer the spectacular gaming performance we expected. This month it's the turn of CrossfireX, ATi's rival multi-GPU technology, to go under the microscope in the menacingly monikered Fusion Venom.

Graphical power is provided by a pair of Radeon HD 3870 X2 cards: four GPUs chilled by two double-height coolers that brushed aside our High 1,600 x 1,200 Crysis benchmark with a remarkable score of 41fps.

At Very High quality and the same resolution the Fusion Venom was just as impressive, scoring 31fps - the first we've seen to crack the 30fps barrier with every option at maximum. Even at the higher 1,920 x 1,200 resolution, an average of 27fps means you'll only see the frame rate stutter in more demanding scenes.

These scores compare well with other recent machines: the Dell XPS 630 costs £382 more - albeit with a stunning 24in monitor included - but its pair of GeForce 8800 GT cards averaged 2fps slower in both of those last two extreme tests. Chillblast's own Fusion Trident served up patchy performance that isn't worth the extra £561, and the leading machines in our Ultimate PC Labs included GeForce 8800 Ultra or GTX cards that don't offer the graphical power available here.

The Fusion Venom's processor is somewhat overshadowed by the graphics hardware, but it's no less impressive. A Core 2 Quad Q6600 follows in the long line of Intel parts that are capable overclockers - three machines in the Ultimate PC Labs featured similar performance boosts - but increasing the clock speed to a whopping 3.4GHz (as this machine has) from the standard 2.4GHz, is unprecedented. It's the biggest increase we've seen on this processor, and helps propel the Chillblast to a dazzling 2D benchmark score of 1.81 - not quite the highest we've seen but impressive nonetheless.

It's a little odd to include 4GB of RAM with 32-bit Vista included, however. Each of the monstrous graphics cards reserves a gigabyte of the operating system's 4GB limit, meaning only 2GB of system memory will ever be available for use. Including Vista 64-bit would have solved the problem, though.

The well-built case - Cooler Master's imposing Dominator - provides efficient cooling, keeping the rest of the innards adequately chilled despite the graphics cards themselves becoming pretty toasty during extended use. It's a power-hungry system: very few machines we've seen recently draw more than the Chillblast's peak of 473W, but that's a drawback you have to contend with if you want this amount of graphical oomph.

The bulky graphics cards and the AC Freezer Pro 7 heatsink make for a cramped interior, but Chillblast has at least tried to maximise airflow. Wires are kept as tidy as possible, although that's difficult when each graphics card requires a pair of power connectors. Three 120mm case fans - one at each end of the case and another on the ceiling - also help; but this obviously makes the Fusion Venom rather loud during intensive use.

You shouldn't need the two free DIMM slots with 4GB already fitted, but four free 3.5in and 5.5in bays cater for added storage and drives. The 3.5in bays helpfully face sideways for easy access - and the included 500GB drive is positioned at the top of the stack so as not to disrupt airflow. Free SATA ports, though, sit directly beneath the graphics cards, complicating upgrades; the eSATA port on top of the case may be a more viable option.