Dell Inspiron 3891 vs. Dell OptiPlex 7070 SFF
Comparison and Differences
Differences between Dell Inspiron 3891 and Dell OptiPlex 7070 SFF
If you are looking for a more modern desktop, then you should go with the Dell Inspiron 3891 which was released in 2021. The Dell OptiPlex 7070 SFF is older and entered production in 2019.
If you are looking for the smaller form factor the Dell OptiPlex 7070 SFF is the right one for you. It is smaller than the Dell Inspiron 3891 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 Inspiron 3891 as it is running a newer generation CPU. This is not to say that Dell OptiPlex 7070 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.
Memory
The Dell OptiPlex 7070 SFF has 4 RAM slots while the Dell Inspiron 3891 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 Inspiron 3891 is using the faster 2933 MT/s RAM. The Dell OptiPlex 7070 SFF 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 64 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
In total the Dell OptiPlex 7070 SFF has 10 USB ports. The Dell Inspiron 3891 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 7070 SFF, is that it has 1 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell Inspiron 3891 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 7070 SFF comes with 2 ports, while the Dell Inspiron 3891 has only 1. If you are planning to use multiple monitors, the Dell OptiPlex 7070 SFF is the better choice.
The Dell Inspiron 3891 comes with an HDMI port, while the Dell OptiPlex 7070 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 7070 SFF is better equipped as it comes with 3 SATA slot(s), while the Dell Inspiron 3891 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
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 7070 SFF comes with a decent 200 Watt PSU, but the Dell Inspiron 3891 has a more powerful one rated at 260 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.