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Dell Alienware X51 review

Our Rating :
Price when reviewed : £799
inc VAT

A neat design, but the X51 could do with a more powerful graphics card


3GHz Intel Core i5-2320, 8GB RAM, N/A display, Windows 7 Home Premium 64-bit

The X51 is a compact gaming PC from Dell’s premium Alienware brand. It’s about the same size as an Xbox Elite, and has a selection of clever features.

The slim case is fairly understated as far as Alienware designs go, with just a glowing alien head and LED-lit clear side panels. The gloss front panel contrasts nicely with the matte sides, and the case is designed to be stood upright or on its side – you can swivel the alien head to match a horizontal aspect.

Dell Alienware X51

The front of the case gives you the standard twin USB and headphone and microphone ports, but round the back things are more interesting; the X51 is geared up to plug into your home cinema system as well as a standard PC monitor, keyboard and mouse. To this end there are HDMI and optical and coaxial S/PDIF outputs, so you’re covered for most HDTVs and surround sound systems, as well as twin DVI outputs on the graphics card and 7.1 analogue outputs to connect to PC speaker sets. You also get built in gigabit Ethernet and 802.11n wireless networking.

There are four main models of X51. The base £649 version has a dual-core Intel Core i3-2120 processor, 4GB RAM and an Nvidia GeForce GTX 545 graphics card, the £749 model above has an upgrade to a quad-core Core i5-2320, while the top two models have faster GeForce GTX 555 graphics cards, 8GB RAM and quad-core Core i5-2320 and Core i7-2600 chips for £799 and £899 respectively.

Dell Alienware X51

We have the £799 model, which we feel is the sweetspot. Its 3GHz i5-2320 processor is quick enough for even intensive 2D tasks, as shown by an overall score of 97 in our benchmarks. The X51’s Nvidia GTX 555 graphics card is an OEM model which you can’t buy separately. It’s slightly less well-specified than a GeForce GTX 560Ti, with 288 CUDA cores compared to 384 and a 1.5GHz rather than 1.6GHz core clock speed.

The X51 showed reasonable performance in our game tests. 40fps in Dirt 3 at 1,920 x 1,080 and Ultra detail gives you smooth gameplay, but the PC didn’t cope so well with our intensive Crysis 2 test, managing just 16.4fps at 1,920 x 1,080 and Ultra detail. We had to turn Crysis 2 down to “Very High” settings, losing all the fancy tessellation effects, to get a smooth 34.1fps.

Dell Alienware X51

Fortunately, despite its small dimensions, the PC is fairly easy to upgrade. The side panel slides off and gives you access to the twin memory slots, and to change the graphics card you just need to remove a couple of screws and slide the card out of a metal tray. The X51 has two six-pin PCI Express plugs, and we had no problems fitting a far more powerful AMD Radeon HD 6870 graphics card, which led to a large improvement in our graphics benchmark scores. The 1TB hard disk is also easy to get at, but as there’s only room for one disk you’ll need to replace the old one if you upgrade.

The X51’s main problem is price. You could build a PC around a Shuttle SH67H3 barebones with an Intel Core i5-2320 processor, 8GB RAM, a 1TB hard disk and an AMD Radeon HD 7770 graphics card, which will give you similar performance to the X51 in a chassis almost as compact for around £620. The Alienware X51 is a neat design and would make a great living room PC for some gaming – we just wish its 3D performance was more impressive.

Basic Specifications

Rating ***
Processor Intel Core i5-2320
Processor external bus 100MHz
Processor multiplier x30
Processor clock speed 3GHz
Processor socket LGA1155
Memory 8
Memory type PC3-10600
Maximum memory 16GB
Motherboard Custom
Motherboard chipset Intel H61 Express


USB2 ports (front/rear) 2/6
Firewire ports (front/rear) 0/0
eSATA ports (front/rear) 0/0
Wired network ports 1x 10/100/1000
Wireless networking support 802.11b/g/n

Internal Expansion

Case mini PC
PCI slots (free) 0
PCI-E x1 slots (free) 0
PCI-E x16 slots (free) 1 (0)
Free Serial ATA ports 1
Free memory slots 0
Free 3.5in drive bays 0

Hard Disk

Hard disk model(s) Seagate Barracuda ST31000524AS
Interface SATA3
Total storage capacity 1,024GB


Graphics card(s) Nvidia GeForce GTX 555
Graphics/video ports 2x DVI, 1x HDMI, 1x mini HDMI


Sound Realtek HD Audio
Sound outputs 7.1 line out, coaxial S/PDIF out, optical S/PDIF out
Speakers none

Removable Drives

Supported memory cards none
Optical drive type(s) DVD+/-RW DL


Screen model none
Native resolution N/A
Screen inputs N/A

Other Hardware

Keyboard Alienware Multimedia Keyboard
Mouse Alienware Optical Mouse


Software included none
Operating system Windows 7 Home Premium 64-bit
Operating system restore option Windows disc

Buying Information

Warranty one-year RTB
Price £799

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