HP ProDesk 400 G2.5 SFF vs. HP ProDesk 600 G4 SFF
Comparison and Differences
Differences between HP ProDesk 400 G2.5 SFF and HP ProDesk 600 G4 SFF
If you are looking for a more modern desktop, then you should go with the HP ProDesk 600 G4 SFF which was released in 2018. The HP ProDesk 400 G2.5 SFF is older and entered production in 2014.
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 HP ProDesk 600 G4 SFF as it is running a newer generation CPU. This is not to say that HP ProDesk 400 G2.5 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.
Memory
The HP ProDesk 600 G4 SFF has 4 RAM slots while the HP ProDesk 400 G2.5 SFF 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 HP ProDesk 600 G4 SFF is using the faster 2666 MT/s RAM. The HP ProDesk 400 G2.5 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 HP ProDesk 600 G4 SFF as it has the ability to run 64 GB of RAM. The HP ProDesk 400 G2.5 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 HP ProDesk 600 G4 SFF has 11 USB ports. The HP ProDesk 400 G2.5 SFF is inferior in this regard and packs 8 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 SFF, is that it has 5 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the HP ProDesk 400 G2.5 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.
DisplayPort is crucial for any desktop machine. It is good to see that both models are featuring DisplayPorts. However, the HP ProDesk 600 G4 SFF comes with 2 ports, while the HP ProDesk 400 G2.5 SFF has only 1. If you are planning to use multiple monitors, the HP ProDesk 600 G4 SFF is the better choice.
None of the models has an HDMI port. If your monitor supports only the HDMI interface, you will need to buy an adapter. Such adapters are cheap so nothing to worry about.
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.
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 HP ProDesk 600 G4 SFF. Sadly, the HP ProDesk 400 G2.5 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 180 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.
Motherboard
