Acer Veriton ES2740g vs. Dell OptiPlex 7040M
Comparison and Differences
Differences between Acer Veriton ES2740g and Dell OptiPlex 7040M
If you are looking for a more modern desktop, then you should go with the Acer Veriton ES2740g which was released in 2019. The Dell OptiPlex 7040M is older and entered production in 2015.
If you are looking for the smaller form factor the Dell OptiPlex 7040M is the right one for you. It is smaller than the Acer Veriton ES2740g 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 Acer Veriton ES2740g 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 Acer Veriton ES2740g 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
In total the Acer Veriton ES2740g has 8 USB ports. The Dell OptiPlex 7040M 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. 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.
Unfortunately, only the Dell OptiPlex 7040M has a DisplayPort. The Acer Veriton ES2740g does not have one? Don't worry though, nowadays video adapters are cheap and you can get almost any combination of conversion types.
In case your monitor supports HDMI only, you will be happy to hear that both models come with an HDMI port.
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 Acer Veriton ES2740g is better equipped as it comes with 2 SATA slot(s), while the Dell OptiPlex 7040M has 1 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 7040M comes with a decent 65 Watt PSU, but the Acer Veriton ES2740g 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.