Verdict: All the latest components, but it's hot, noisy and not as stable as it should be.

Each year, we like to invite a company that has not participated before to take part in the Dream PC Labs test, and this year that honour fell to Gladiator. Our choice was prompted by the impressive pre-overclocked systems that the company has sent to us for review over the past few years.

Like most Dream PCs, the Poseidon sports two water-cooled graphics cards. Rather disappointingly, though, they're standard off-the-shelf components and aren't fitted with custom waterblocks. For example, they're pre-fitted with Innovatek Chill-Matic waterblocks by EVGA, so all Gladiator has done is connect the waterblocks to the tubing. The CPU, meanwhile, is fitted with a diminutive Alphacool NexXxos XP waterblock that shares the same tubing as used by the graphics cards. This means that all three components dump heat into the dual 120mm-fan radiator mounted on its side in the lower half of the case.

This is a pretty good location for the radiator, but it simply isn't large enough to dissipate heat quickly enough. In fact, the radiator struggles so much that the CPU reached a ludicrous 92ûC during our 15-minute stress test. After a few more minutes, the graphics cards overheated and filled the screen with horizontal interference lines. In addition, the whole case became hot, while the metal caps on the ends of the enormous roof-mounted Alphacool Cape Coolplex 75 reservoir became too hot to touch. As if that isn't bad enough, if you're sitting to the left of the Poseidon so you can look through the window in the side panel, the hot air from the radiator vents directly over where your hand holds the mouse. In contrast to last year's silent Quiet PC Jaguar, the Poseidon is very loud and pretty unpleasant to sit next to for any length of time. Noise might be a desirable characteristic for a high-performance car, but it definitely isn't a feature you want to find in a high-performance PC.

The Poseidon clearly struggles to keep its temperature under control, which is hardly surprising when you consider the components that Gladiator has squeezed inside the SilverStone TJ07 case. The CPU is every overclocker's favourite - the Intel Core 2 Extreme QX6850. This normally runs at 3GHz, but in the Poseidon, it runs at 3.33GHz. This small overclock is achieved by boosting the CPU multiplier from 9 to 10. The 4GB of Patriot DDR2 RAM is rated at up to 1,150MHz; in the Poseidon, however, it chugs along at 800MHz, as the Asus Striker Extreme motherboard wouldn't run the RAM faster than this with four DIMMs fitted. While 4GB of RAM might sound like overkill, the Poseidon comes with the 64-bit version of Windows Vista Ultimate and, unlike the 32-bit version, it can take full advantage of this amount of RAM. This is useful, as 1.536GB would have been set aside for the two EVGA GeForce 8800 Ultra Black Pearl graphics cards due to the need for memory-mapped access if Gladiator had used a 32-bit OS. The EVGA cards are configured to run together in SLI but, while the GPUs are clocked higher than on standard GeForce 8800 Ultra cards, the RAM was set to run slightly slower.

The WD Raptor X may have been eclipsed by the SSD, but it's still one of the fastest hard disks around, so the Poseidon is fast at loading games and applications. If, like most enthusiasts, you have a huge collection of MP3s and downloads to store, the two 1TB Hitachi Deskstar 7K1000 hard disks will probably be a very attractive proposition - although Gladiator has taken the risky decision to link them in a single, massive, fault-intolerant RAID 0 array. Also along for the ride are two identical Pioneer Blu-ray writers. Quite what you're supposed to do with two identical drives is beyond us; long gone are the days when you performed CD-to-CD copying, and you certainly can't watch two Blu-ray movies at the same time. A Dream PC is supposed to be an ultimate PC and not want for anything, but two expensive optical drives is just plain silly.

All these components are housed in a SilverStone TJ07 case that's painted Imperial Blue, although the bezels on the optical drives don't match the colour of the case. Other components include a full suite of high-quality Logitech peripherals, including a G15 keyboard, MX Revolution mouse and 5.1 Z-5500 Digital speakers. The speakers are fed by a Sound Blaster X-Fi Xtreme Gamer Fatal1ty Pro, the-top-of-the-range X-Fi card, bar the Elite Pro and Platinum Fatal1ty Champion, which only differ in having external breakout boxes. Display duties are handled by a BenQ FP241WZ, a 24in TFT with a native 1,920 x 1,200 resolution. While this is the same resolution as that of the monitors supplied with the other Dream PCs, images appear cramped on it compared with the 27in displays supplied with the Dell, Scan and Vadim PCs.

Performance

The QX6850 is a fast CPU, especially when overclocked, and it certainly isn't hurt by being accompanied by 4GB of RAM, 64-bit Vista and a Raptor X. However, although we know that our new Media Benchmarks 2007 are compatible with 64-bit Vista, the image editing test persistently failed at random points on the Poseidon, so we were only able to run the video encoding and multitasking tests. As such, we were unable to calculate an overall score for the Poseidon. In the video encoding test, the Poseidon scored an impressive 1,793, just a few points ahead of the Dell, and in multitasking, it scored 889, once again just beating the Dell. This is no doubt partly due to the Poseidon's faster Raptor X hard disk but, as we discovered a few months ago, the higher FSB of the latest quad-core Intel CPUs also helps.

Vista and SLI aren't the best of friends, 64-bit Vista in particular, so the Poseidon proved to have very variable game performance. For example, while the Poseidon failed to achieve a smooth frame rate in World in Conflict, the similarly specified Scan White Cobra was able to render the game at more than double the speed. Even so, the Poseidon was able to play most of our test games smoothly at 1,920 x 1,200 with all the detail settings cranked up to maximum, apart from Flight Simulator X - this game proved to be an insurmountable challenge for all of this year's Dream PCs.

Conclusion

While the Poseidon boasts impressive performance, the choice of 64-bit Vista means that many applications and games refuse to work, or run slower than they do in 32-bit Vista or Windows XP.

Fundamentally, however, the Poseidon fails to entice, as its cooling system struggles to dissipate the heat generated by the quad-core CPU and two graphics cards. Poseidon was revered as the god of the sea and earthquakes by the Greeks. Gladiator's Poseidon may be water-cooled but, a bit like an earthquake, it's also noisy and more than a little unstable.

• Gaming Headsets - 26th September 2008
• Dream PCs - 24th September 2008
• Headphones - 12th September 2008
• Media PC components - 22nd August 2008
• PSUs - 14th July 2008
• Multi-GPU graphics - 20th June 2008
• CPU water cooling - 17th June 2008

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• DFI Lanparty DK P45-T2RS PLUS - Motherboards
• Hyundai W240D-PVA - TFT monitors
• Intel X25-M Mainstream SATA SSD - Hard disks / storage
• S.T.A.L.K.E.R. Clear Sky - Games
• LanCool Metal-Boned K10 - Cases
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