Alienware X51 R3 vs. Dell OptiPlex 7040 SFF

Differences between Alienware X51 R3 and Dell OptiPlex 7040 SFF

Both computers, the Dell OptiPlex 7040 SFF and the Alienware X51 R3, were released during the same year - 2015.

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

Processor

The two models have the same generation of Intel processors. We think that the 6 generation of Intel Processors have enough power to execute all of the home and office tasks that most people will care to do.

Memory

The Dell OptiPlex 7040 SFF has 4 RAM slots while the Alienware X51 R3 has only 2 slot(s). This is not something to worry about. Just make sure you take it into consideration when planning how much RAM you are going to use.

None of the desktops has an advantage when it comes to the speed of the RAM being used. Both models support RAM speeds of up to 2133. Additionally, if you will be needing a lot of RAM, better go for the Dell OptiPlex 7040 SFF as it has the ability to run 64 GB of RAM. The Alienware X51 R3 can do a bit less at max 32 GB. Most of the times, this should be sufficient for the majority of users.

Ports

In total the Dell OptiPlex 7040 SFF has 10 USB ports. The Alienware X51 R3 is inferior in this regard and packs 8 USB ports. In any case, if you miss USB ports, you can always purchase a USB hub. What is nice about the Alienware X51 R3, is that it has 2 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell OptiPlex 7040 SFF has no such port, thus restricting your transfer speeds significantly. For people who want to use external drives on regular basis, this might be an issue.

DisplayPort is crucial for any desktop machine. It is good to see that both models are featuring DisplayPorts. However, the Dell OptiPlex 7040 SFF comes with 2 ports, while the Alienware X51 R3 has only 1. If you are planning to use multiple monitors, the Dell OptiPlex 7040 SFF is the better choice.

The Dell OptiPlex 7040 SFF comes with an HDMI port, while the Alienware X51 R3 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 slots are located on the motherboard and it is where SSD, HDD and Optical Disk Drives are connected. Each of the two models being compared have 3 SATA slot(s). Keep in mind that having too few SATA slots might limit your options for connecting additional memory drives.

If you want the fastest transfer speeds for your SSD, an M.2 interface is crucial. Thus, if the M.2 SSD slot is a mandatory requirement for you, go with the Dell OptiPlex 7040 SFF. Sadly, the Alienware X51 R3 has no such slot, and you will be forced to use the SATA interface instead.

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 7040 SFF comes with a decent 180 Watt PSU, but the Alienware X51 R3 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