Dell OptiPlex 5040 SFF vs. Dell OptiPlex 5090 M
Comparison and Differences
Differences between Dell OptiPlex 5040 SFF and Dell OptiPlex 5090 M
If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 5090 M which was released in 2021. The Dell OptiPlex 5040 SFF is older and entered production in 2015.
If you are looking for the smaller form factor the Dell OptiPlex 5090 M is the right one for you. It is smaller than the Dell OptiPlex 5040 SFF 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 M as it is running a newer generation CPU. This is not to say that Dell OptiPlex 5040 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.
Memory
The Dell OptiPlex 5040 SFF has 4 RAM slots while the Dell OptiPlex 5090 M 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 5090 M is using the faster 3200 MT/s RAM. The Dell OptiPlex 5040 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 OptiPlex 5090 M as it has the ability to run 64 GB of RAM. The Dell OptiPlex 5040 SFF can do a bit less at max 16 GB. Most of the times, this should be sufficient for the majority of users.
Ports
In total the Dell OptiPlex 5040 SFF has 10 USB ports. The Dell OptiPlex 5090 M is inferior in this regard and packs 6 USB ports. In any case, if you miss USB ports, you can always purchase a USB hub. What is nice about the Dell OptiPlex 5090 M, is that it has 1 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell OptiPlex 5040 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.
The DisplayPort is usually the more popular video port used with desktops and laptops, while the HDMI is used predominantly in consumer electronics. That's why, it is good to see that both of the models come with a DisplayPort.
The Dell OptiPlex 5040 SFF comes with an HDMI port, while the Dell OptiPlex 5090 M 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.
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 M comes with a decent 130 Watt PSU, but the Dell OptiPlex 5040 SFF has a more powerful one rated at 180 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
