Alienware X51 R2 vs. Dell OptiPlex 390 SFF

Comparison and Differences

Alienware_X51_R2.jpg case front and back pannelDell_OptiPlex_390_SFF.jpg case front and back pannel
Model
Form factorSmall GamingSmall
CPU optionsIntel Gen4 i3/i5/i7;Intel Gen2 i3/i5/i7; Celeron; Pentium;
ChipsetH87H61
Dedicated GPU *GeForce GTX 1650 SuperGeForce GTX 1650 Low Profile
RAMDIMM DDR3-1600 DIMM DDR3-1333
RAM slots22
RAM speed1600 MT/s1333 MT/s
RAM max16 GB8 GB
USB ports(6x) USB 3.0 Type A; (2x) USB-A 2.0; (8x)USB-A 2.0;
Video portsHDMI 1.4b;HDMI 1.2; VGA;
Other portsRJ45; Headset; Line-Out; Line-In; S/PDFI optical/analog;RJ45; Hdph; Line-Out; Line-In and Mic; Mic; PS2/COM;
Optional portsN.A.N.A.
SATA ports32
PCI slotsPCIe 3.0 x16;PCIe 2.0 x16; PCIe 2.0 x1;
M.2 slotsN.A.N.A.
Drive bays(2x) 2.5in; 3.25in; 5.25in;3.5in; 5.25in(slim);
PSU240/330 W240 W
Weight5.49 kgs (12.10 lbs)5.70 kg (12.57 lb)
Released20132011
Manuallinklink
Price**Check PriceCheck Price

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* Dedicated GPU warning: Check if your particular power supply model has enough power. Additionally some PSUs don't come with an auxiliary PCIe power connector and you may need to buy a SATA to PCIe power adapter.

Differences between Alienware X51 R2 and Dell OptiPlex 390 SFF

If you are looking for a more modern desktop, then you should go with the Alienware X51 R2 which was released in 2013. The Dell OptiPlex 390 SFF is older and entered production in 2011.

Both models have the same form factor, meaning reoughtly they have the same phiysical size and form.

Processor

Usually the newer the generation of the CPU, the better the performance and efficiency is. If your budget allows it, you should go with the Alienware X51 R2 as it is running a newer generation CPU. This is not to say that Dell OptiPlex 390 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.

Memory

Both models have have equal amount of ram slots (2 RAM). Usually two RAM slots are more than enough for most cases. However, the count should be taken into account when planning how much and what combination of RAM you are going to need for your system.

The Alienware X51 R2 is using the faster 1600 MT/s RAM. The Dell OptiPlex 390 SFF is slower by supporting RAM speeds of up to 1333 MT/s. Additionally, if you will be needing a lot of RAM, better go for the Alienware X51 R2 as it has the ability to run 16 GB of RAM. The Dell OptiPlex 390 SFF can do a bit less at max 8 GB. Most of the times, this should be sufficient for the majority of users.

Ports

Both models have the same amount of USB ports for total count of 8. If this is not enough, using a USB hub is always a viable option. None of the desktop models has a USB 3.1 port (10Gb/s), so if you need a fast connection to your peripherals, like external Solid State Drive, you will need to look elsewhere.

Unfortunately, only the Alienware X51 R2 has a DisplayPort. The Dell OptiPlex 390 SFF does not have one? Don't worry though, nowadays video adapters are cheap and you can get almost any combination of conversion types.

The Dell OptiPlex 390 SFF comes with an HDMI port, while the Alienware X51 R2 does not support the interface. Of course missing HDMI port is something that can be easily fixed with a good adapter (e.g. DisplayPort to HDMI).

SATA ports are placed on the system board and it is where you connect your HDD, SSD and Optical Disk Drives. More SATA slots will allow you to have more drives running at the same time. In this regard the Alienware X51 R2 is better equipped as it comes with 3 SATA slot(s), while the Dell OptiPlex 390 SFF has 2 slot(s).

M.2 SSD interface allows you to transfer data with higher speeds compared to the old SATA interface. Unfortunately, neither the Dell OptiPlex 390 SFF, nor the Alienware X51 R2 has one. However, you can still use a SATA SSD drive which should give you satisfactory performance.

Make sure that the available M.2 slot supports the PCIe (also called NVMe) interface. This is important as there are M.2 slots which support only the inferior SATA III interface. For comparison, the SATA III interface has max speeds of 6Gb/s, while the PCIe 3.0 x4 will support speeds up to 32Gb/s!

Power Supply

Having a Power Supply Unit with high power rating is important, if you are going to use components which require extra power. The Dell OptiPlex 390 SFF comes with a decent 240 Watt PSU, but the Alienware X51 R2 has a more powerful one rated at 330 Watts. Choosing either one depends on your specific requirements and use case. Also don't forget that some models might have more than one PSU option - try to always get the most powerful one, especially if you plan to upgrade to a powerful GPU.

Motherboard

Alienware_X51_R2_motherboard.jpg motherboard layoutDell_OptiPlex_390_SFF_motherboard.jpg motherboard layout