Dell XPS 8940 vs. HP EliteDesk 800 G3 Tower
Comparison and Differences
Differences between Dell XPS 8940 and HP EliteDesk 800 G3 Tower
If you are looking for a more modern desktop, then you should go with the Dell XPS 8940 which was released in 2020. The HP EliteDesk 800 G3 Tower is older and entered production in 2017.
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 Dell XPS 8940 as it is running a newer generation CPU. This is not to say that HP EliteDesk 800 G3 Tower 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 HP EliteDesk 800 G3 Tower is slower by supporting RAM speeds of up to 2400 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 HP EliteDesk 800 G3 Tower can do a bit less at max 64 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 HP EliteDesk 800 G3 Tower 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 HP EliteDesk 800 G3 Tower comes with 2 ports, while the Dell XPS 8940 has only 1. If you are planning to use multiple monitors, the HP EliteDesk 800 G3 Tower is the better choice.
The Dell XPS 8940 comes with an HDMI port, while the HP EliteDesk 800 G3 Tower 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 HP EliteDesk 800 G3 Tower is better equipped as it comes with 5 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
Looking at the Power Supply Unit (PSU) of the two models we don't see any differences. For either of them you get a maximum power of 500 Watts. However be careful, many models have more than one power supply option. When buying your computer, it is a good idea to get a version with the most powerful PSU. This will potentially allow you to upgrade to a more powerful GPU for example.