Dell OptiPlex 5040 MT vs. Dell OptiPlex 7010 SFF
Comparison and Differences
Differences between Dell OptiPlex 5040 MT and Dell OptiPlex 7010 SFF
If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 5040 MT which was released in 2015. The Dell OptiPlex 7010 SFF is older and entered production in 2012.
If you are looking for the smaller form factor the Dell OptiPlex 7010 SFF is the right one for you. It is smaller than the Dell OptiPlex 5040 MT 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 5040 MT as it is running a newer generation CPU. This is not to say that Dell OptiPlex 7010 SFF 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.
None of the desktops has an advantage when it comes to the speed of the RAM being used. Both models support RAM speeds of up to 1600. Additionally, if you will be needing a lot of RAM, better go for the Dell OptiPlex 7010 SFF as it has the ability to run 32 GB of RAM. The Dell OptiPlex 5040 MT can do a bit less at max 16 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. None of the desktop models has a USB 3.1 port (10Gb/s), so if you need a fast connection to your peripherals, like external Solid State Drive, you will need to look elsewhere.
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 MT comes with an HDMI port, while the Dell OptiPlex 7010 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 5040 MT is better equipped as it comes with 4 SATA slot(s), while the Dell OptiPlex 7010 SFF has 3 slot(s).
If you want the fastest transfer speeds for your SSD, an M.2 interface is crucial. Thus, if the M.2 SSD slot is a mandatory requirement for you, go with the Dell OptiPlex 5040 MT. Sadly, the Dell OptiPlex 7010 SFF has no such slot, and you will be forced to use the SATA interface instead.
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 240 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.