Verdict: Two graphics cards aren't always better than one
Continuing its astrological naming theme (we've already seen two Cepheus machines), Vadim's latest PC is named after the Cetus constellation, which includes the Mira star, the first variable star to be discovered. As a variable star, Mira changes brightness over a period of 331.65 days, and it turns out that such a changeable namesake is appropriate for this variable-performance PC.
Vadim has designed the Cetus to be much cheaper to produce than most of its PCs, which typically retail for between £4,000 and £5,000. The most obvious cost-cutting measure is the presence of a non-Extreme Edition dual-core CPU in the form of a 2.4GHz Core 2 Duo E6600. However, in true Vadim style, the CPU is overclocked to within a hair's breadth of its life - 3.6GHz to be precise. This awesome 67 per cent overclock is achieved by a very generous 1.6V overvolt and a 400MHz (1.6GHz effective) FSB. Such a huge overvolt is only possible because the CPU sits underneath a massive Swiftech Apogee GT waterblock, which is cooled by a dual and triple 120mm-fan radiator. To keep down costs, Vadim hasn't water-cooled the Intel 975X Northbridge on the Asus P5W DH Deluxe motherboard, although a 40mm fan is screwed to its heatsink. Accompanying this turbocharged CPU is 2GB of OCZ PC2-8500 RAM running at 4 - 4 - 4 - 12 latency timings. As it's part of the Reaper range, each DIMM has a heatpipe leading to a separate heatsink.
The motherboard has two high-speed PCI-E slots, each of which is capable of providing eight PCI-E lanes, and the Cetus is fitted with a pair of Radeon HD 2900XT graphics cards. As the 2900XT is barely a month old, it's good to see that there are enough cards available for PC manufacturers to start building CrossFire PCs. Unlike previous generations of CrossFire, these new cards don't have to faff around with awkward external pass-through cables; instead, they use two small ribbon cables inside the case to link the cards together. Although the cards are fitted with Swiftech MCW60 waterblocks, these only cool the GPUs, not the RAM. To prevent the RAM chips from staging an impression of Mount Vesuvius, an 80mm fan blows cool air over both graphics cards. The GPU waterblocks share the same cooling loop as the CPU, hence the two large radiators. In keeping with Vadim's reputation for heavily overclocked PCs, the frequency of both GPUs has been raised from 742MHz to 848MHz, and the RAM from 828MHz (1.656GHz effective) to 848MHz (1.696GHz effective). This is slightly lower than the overclock we've previously achieved on air-cooled 2900XT cards and, apparently, is because the cards won't overclock as far in CrossFire as in single-card mode.
As the Cetus is intended to be a cost-effective high-end PC, Vadim has installed a Samsung SpinPoint T166 hard disk, so you don't have to sit around waiting for games and applications to load. This not only provides 500GB of space for your data, but is extremely fast too - it was quicker than the WD Raptor X at loading games in our recent hard disk Labs test. This drive is accompanied by a dual-layer Samsung DVD burner and a front-mounted memory card reader. If these drives aren't enough for your burgeoning collection of downloads and other gubbins then there are several free bays for adding extra disk drives.
As the 2900XT graphics cards are so power-hungry, the Cetus is fitted with a monstrous 1kW Enermax Galaxy PSU. This remains the best 1kW PSU we've tested, combining perfect stability and good efficiency with a quiet cooling fan and modular cables. Even so, the Vadim drew a stonking xxxW from the mains when running 3DMark06 at full pelt. No high-end gaming PC would be complete without an X-Fi sound card, and the Cetus doesn't disappoint, as it's fitted with the Extreme Gamer Fatal1ty Pro edition. All of these components are housed inside a massive SilverStone Temjin TJ07 case, which has been customised with a viewing window in the left side panel, revealing the extraordinarily neatly built water-cooling system, and a series of LEDs and cold-cathode lamps. As usual for a Vadim PC, a well-hidden mCubed T-Balancer bigNG fan controller adjusts the speed of the system's ten fans according to the temperature reading of several thermal probes dotted around the case. As a result, the Cetus is astonishingly quiet, making it hard to believe that it's cooled by so many fans.
Performance
Although the Cetus is fitted with 'only' a dual-core CPU, it's very heavily overclocked and, as such, performs very well. For example, despite also being water-cooled, the same CPU in the Scan 3XS OC-GTS was only overclocked to 3GHz. As a result, the Scan scored 1.94 overall in our Media Benchmarks, while the Cetus scored 2.41. The Cetus also fares well against many quad-core CPU-equipped PCs, as most applications aren't able to take advantage of all four cores. However, if you're a keen folder or spend a lot of time encoding DVDs, it could be worth asking Vadim to install a cheap quad-core CPU in the Cetus, and finding out how far the company could overclock it.
The main selling point of the Cetus is, of course, the pair of Radeon HD 2900XT graphics cards running together in CrossFire. Unfortunately, we found many games ran slower in CrossFire mode than with a single card. For example, in CrossFire, the minimum frame rate in Need for Speed: Carbon at 1,280 x 1,024 with 2x AA and AF enabled was just 32fps, with an average of 54fps; with CrossFire disabled, the frame rates jumped to 48fps and 64fps respectively. Despite a whole raft of patches, S.T.A.L.K.E.R. still doesn't run stably in Vista, making testing impossible. However, F.E.A.R., Company of Heroes and Oblivion proved to be much better written. Although CrossFire boosted the average frame rate from 53fps to 94fps in F.E.A.R. at 1,920 x 1,200 with 4x AA and 16x A, the minimum frame rate wouldn't budge from 20fps, making the game jerky and unplayable.
Company of Heroes proved to be much more friendly, with the average and minimum frame rates nearly doubling when CrossFire was enabled. Oblivion also ran much faster with CrossFire enabled than it did on a single card; the frame rate in our Arena battle jumped from a minimum of 41fps to 48fps, although the average only crept forward from 64fps to 65fps. However, the Cetus lost the plot entirely when trying to render outside areas.
Conclusion
While the super-overclocked CPU, RAM and excellent choice of hard disk ensure that the Cetus performs brilliantly in 2D applications, the choice of two Radeon HD 2900XT has both plus and minus points. On the plus side, the graphics cards are DirectX 10-compatible and, since they're water-cooled, they're very quiet. However, due to ATi's decision to optimise the Radeon HD 2000-series architecture for shader AA rather than traditional geometry AA, the cards perform poorly when running a game with lots of AA and AF. In addition, as we discovered, CrossFire still doesn't work very well in many games, running slower than they did with a single card in some cases. As such, if you're seriously interested in the Cetus, we'd recommend ordering it with a single graphics card.
