Dell OptiPlex 3070 SFF vs. Dell OptiPlex 5080 SFF
Comparison and Differences
Differences between Dell OptiPlex 3070 SFF and Dell OptiPlex 5080 SFF
If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 5080 SFF which was released in 2020. The Dell OptiPlex 3070 SFF is older and entered production in 2019.
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 OptiPlex 5080 SFF as it is running a newer generation CPU. This is not to say that Dell OptiPlex 3070 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.
Memory
The Dell OptiPlex 5080 SFF has 4 RAM slots while the Dell OptiPlex 3070 SFF 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.
The Dell OptiPlex 5080 SFF is using the faster 2933 MT/s RAM. The Dell OptiPlex 3070 SFF is slower by supporting RAM speeds of up to 2666 MT/s. Additionally, if you will be needing a lot of RAM, better go for the Dell OptiPlex 5080 SFF as it has the ability to run 128 GB of RAM. The Dell OptiPlex 3070 SFF 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 5080 SFF has 10 USB ports. The Dell OptiPlex 3070 SFF 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 Dell OptiPlex 5080 SFF, is that it has 1 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell OptiPlex 3070 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 5080 SFF comes with 2 ports, while the Dell OptiPlex 3070 SFF has only 1. If you are planning to use multiple monitors, the Dell OptiPlex 5080 SFF is the better choice.
The Dell OptiPlex 3070 SFF comes with an HDMI port, while the Dell OptiPlex 5080 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 5080 SFF is better equipped as it comes with 3 SATA slot(s), while the Dell OptiPlex 3070 SFF has 2 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 200 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.