Dell OptiPlex 7040M vs. Dell OptiPlex 7070M
Comparison and Differences
Differences between Dell OptiPlex 7040M and Dell OptiPlex 7070M
If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 7070M which was released in 2019. The Dell OptiPlex 7040M is older and entered production in 2015.
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 7070M as it is running a newer generation CPU. This is not to say that Dell OptiPlex 7040M is bad - it can still run some powerful CPUs, albeit being an older generation.
Memory
Both models have have equal amount of ram slots (2 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 OptiPlex 7070M is using the faster 2666 MT/s RAM. The Dell OptiPlex 7040M is slower by supporting RAM speeds of up to 2133 MT/s. In addition, you will be able to install the same amount of RAM in both models, and most probably 32 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
Both models have the same amount of USB ports for total count of 6. If this is not enough, using a USB hub is always a viable option. What is nice about the Dell OptiPlex 7070M, is that it has 1 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell OptiPlex 7040M 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 7070M comes with 2 ports, while the Dell OptiPlex 7040M has only 1. If you are planning to use multiple monitors, the Dell OptiPlex 7070M is the better choice.
The Dell OptiPlex 7040M comes with an HDMI port, while the Dell OptiPlex 7070M 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 1 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 7040M comes with a decent 65 Watt PSU, but the Dell OptiPlex 7070M has a more powerful one rated at 130 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.