Dell OptiPlex 5090 SFF vs. Dell XPS 8940
Comparison and Differences
Differences between Dell OptiPlex 5090 SFF and Dell XPS 8940
If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 5090 SFF which was released in 2021. The Dell XPS 8940 is older and entered production in 2020.
If you are looking for the smaller form factor the Dell OptiPlex 5090 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 OptiPlex 5090 SFF as it is running a newer generation CPU. This is not to say that Dell XPS 8940 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 OptiPlex 5090 SFF is using the faster 3200 MT/s RAM. The Dell XPS 8940 is slower by supporting RAM speeds of up to 2666 MT/s. In addition, you will be able to install the same amount of RAM in both models, and most probably 128 GB of RAM will be enough for most people. However, if you will be needing more RAM, make sure to check other desktop models too.
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. Both of the models have USB 3.1 ports which will allow you to exchange data with your peripherals at up to 10Gb/s. This is especially crucial if you are using external drives on a regular basis.
DisplayPort is crucial for any desktop machine. It is good to see that both models are featuring DisplayPorts. However, the Dell OptiPlex 5090 SFF comes with 2 ports, while the Dell XPS 8940 has only 1. If you are planning to use multiple monitors, the Dell OptiPlex 5090 SFF is the better choice.
The Dell XPS 8940 comes with an HDMI port, while the Dell OptiPlex 5090 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 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 Dell OptiPlex 5090 SFF is better equipped as it comes with 4 SATA slot(s), while the Dell XPS 8940 has 3 slot(s).
When your goal is to have the fastest SSD transfer speeds, an M.2 interface is crucial. Thus, it is good that both models have M.2 SSD slots. Today M.2 SSDs are not much more expensive than the average SATA drives, so it really does not make sense to invest in SATA drives anymore.
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 5090 SFF comes with a decent 300 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
