Dell OptiPlex 9020 SFF vs. Dell XPS 8940
Comparison and Differences
Differences between Dell OptiPlex 9020 SFF and Dell XPS 8940
If you are looking for a more modern desktop, then you should go with the Dell XPS 8940 which was released in 2020. The Dell OptiPlex 9020 SFF is older and entered production in 2013.
If you are looking for the smaller form factor the Dell OptiPlex 9020 SFF is the right one for you. It is smaller than the Dell XPS 8940 and will fit more easily under your desk.
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 Dell XPS 8940 as it is running a newer generation CPU. This is not to say that Dell OptiPlex 9020 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 (4 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 Dell XPS 8940 is using the faster 2666 MT/s RAM. The Dell OptiPlex 9020 SFF is slower by supporting RAM speeds of up to 1600 MT/s. Additionally, if you will be needing a lot of RAM, better go for the Dell XPS 8940 as it has the ability to run 128 GB of RAM. The Dell OptiPlex 9020 SFF can do a bit less at max 32 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 10. If this is not enough, using a USB hub is always a viable option. What is nice about the Dell XPS 8940, is that it has 1 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell OptiPlex 9020 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 9020 SFF comes with 2 ports, while the Dell XPS 8940 has only 1. If you are planning to use multiple monitors, the Dell OptiPlex 9020 SFF is the better choice.
The Dell XPS 8940 comes with an HDMI port, while the Dell OptiPlex 9020 SFF 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 XPS 8940. Sadly, the Dell OptiPlex 9020 SFF 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 9020 SFF comes with a decent 255 Watt PSU, but the Dell XPS 8940 has a more powerful one rated at 500 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
