Alienware X51 R3 (2015)

Updated Slim Gaming Desktop Using Intel 6th Generation Core CPU

Alienware X51 R3 Slim Gaming Desktop PC
Alienware X51 R3. ┬ęDell

After many years of producing their successful slim system, Alienware has decided to return the X51 desktop in favor of the smaller Alpha console like systems. If you are looking for a compact gaming system, be sure to check out the Best Small Form Factor PCs for some more current options.

The Bottom Line

Dell has made some significant improvements to their Alienware X51 R3 slim desktop that helps boost the performance and allow for greater longevity with additional expansion capabilities. The system is a solid small form factor gaming system that offers great gaming while reducing the noise generation compared to previous versions.


  • Well Designed Slim Case
  • Solid Performance
  • Liquid Cooling System Helps Reduce Noise


  • Large External Power Supply Brick
  • High-Performance Gaming Requires Graphics Amplifier External Add-On


  • Intel Core i7-6700K Quad-Core Desktop Processor
  • 8GB PC4-17000 (2133MHz) DDR4 Memory
  • 2TB 7200rpm SATA Hard Drive
  • AMD Radeon R7 370 4GB GDDR5 Graphics Card
  • HDA 5.1 Audio Support
  • Gigabit Ethernet, 802.11ac Wireless
  • Two USB 3.1 Gen2, Four USB 3.1 Gen 1, Two USB 3.0, Alienware Graphics Amplifier, DisplayPort, HDMI, Two DVI
  • 13.5" x 3.7" x 12.5"
  • Windows 10 Home

Review - Alienware X51 R3 (2015)

Alienware's X51 slim desktop has been an excellent gaming desktop system for those that are looking to put a desktop computer into a small space or a living room. The latest R3 version of the system keeps the same basic design and shape as the previous model which is still being sold as an entry level option. While it is not as small as some of the newer small form factor gaming systems, it is still very well designed and accented with the AlienFX lighting that can be adjusted to just about any color you want. Sadly, the power supply is still contained in an external power brick rather than integrated internally which has been the case since it was first introduced.

The big update is to the motherboard and processor for the Alienware X51 R3. The system now uses the latest Intel 6th generation or Skylake processors with the Z170 chipset. For the processor, it uses the Intel Core i7-6700K quad-core processor. This is the highest of the new generation of processors and provides it with an exceptional level of performance. It is clock unlocked meaning it can be overclocked. Dell has also upgraded the cooling to a new internal closed loop liquid cooling solution to help reduce noise and improve cooling. The processor is matched up with new DDR4 memory. It provides a slight boost in performance but provides better future proofing considering that there two memory slots.

Storage has been improved yet stayed the same. Much of this has to do with the default configuration of the systems as sold by Dell. The base configurations still use a traditional hard drive of either two or one terabytes in capacity. These provide more than enough storage but they do limit the performance. Those wanting to get the most out of the system will want to upgrade to either the 256GB or 512GB M.2 solid state drive. This provides much faster boot and application load times than using just a hard drive ut does add significantly to the cost. If you need additional space, there are some exciting options as the system now also supports the USB 3.1 peripheral ports for use with very high-speed external storage. It should be noted on only two of the ports run at the full 10Gbps Generation 2 speed while the remaining four run at the 5Gbps that really is not faster than the USB 3.0 standard. None of the ports use the new Type C connector. Unlike the previous versions of the X51, the R3 version does not include an optical drive to make space for the new cooler.

Graphics have both been improved and remain the same. Due to the small case and internal space for a graphics card, options for an internal card are limited. Users can pick between the AMD Radeon R9 370 or NVIDIA GeForce GTX 960. Both of these cards work perfectly find up to the 1920x1080 resolutions typical of most HDTVs and display monitors. It would have been nice to see an option like the new Radeon R9 Nano but the limited power supplied from the external power brick does cause issues. For those that want to game at 4K resolutions, you do have an upgrade option by purchasing the optional Alienware Graphics Amplifier box. This was designed primarily for their laptop computers but the fairly expensive box then can allow you to purchase a high-performance graphics card for higher resolutions, better detail or multiple monitors.

The lowest price version of the Alienware X51 R3 starts at $1100 but the specifications mentioned in this review start at $1550. This does make the system fairly expensive compare to a traditional desktop system with many of the same features. Compared to many other slim or small form factor gaming systems, it is quite reasonable. The closest in price would likely be the Maingear Drift which is priced nearly the same but offers an internal optical drive. The Digital Storm Bolt 3 is significantly more expensive but offers a much wider range of customization options in terms of internal components.