Dell OptiPlex 7040 SFF vs. HP ProDesk 600 G4 Microtower
Comparison and Differences
Differences between Dell OptiPlex 7040 SFF and HP ProDesk 600 G4 Microtower
If you are looking for the smaller form factor the Dell OptiPlex 7040 SFF is the right one for you. It is smaller than the HP ProDesk 600 G4 Microtower and will fit more easily under your desk.
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 HP ProDesk 600 G4 Microtower as it is running a newer generation CPU. This is not to say that Dell OptiPlex 7040 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.
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.
The HP ProDesk 600 G4 Microtower is using the faster 2666 MT/s RAM. The Dell OptiPlex 7040 SFF 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 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.
In total the HP ProDesk 600 G4 Microtower has 11 USB ports. The Dell OptiPlex 7040 SFF is inferior in this regard and packs 10 USB ports. In any case, if you miss USB ports, you can always purchase a USB hub. What is nice about the HP ProDesk 600 G4 Microtower, is that it has 5 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell OptiPlex 7040 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 7040 SFF comes with an HDMI port, while the HP ProDesk 600 G4 Microtower 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 HP ProDesk 600 G4 Microtower is better equipped as it comes with 4 SATA slot(s), while the Dell OptiPlex 7040 SFF has 3 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!
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 7040 SFF comes with a decent 180 Watt PSU, but the HP ProDesk 600 G4 Microtower has a more powerful one rated at 400 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.