Acer Veriton X2660g vs. Dell Vostro 3900
Comparison and Differences
Differences between Acer Veriton X2660g and Dell Vostro 3900
If you are looking for a more modern desktop, then you should go with the Acer Veriton X2660g which was released in 2018. The Dell Vostro 3900 is older and entered production in 2014.
If you are looking for the smaller form factor the Acer Veriton X2660g is the right one for you. It is smaller than the Dell Vostro 3900 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 X2660g as it is running a newer generation CPU. This is not to say that Dell Vostro 3900 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 X2660g is using the faster 2666 MT/s RAM. The Dell Vostro 3900 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 Acer Veriton X2660g as it has the ability to run 32 GB of RAM. The Dell Vostro 3900 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 8. If this is not enough, using a USB hub is always a viable option. What is nice about the Acer Veriton X2660g, is that it has 2 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell Vostro 3900 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.
Unfortunately, only the Acer Veriton X2660g has a DisplayPort. The Dell Vostro 3900 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 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 4 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 Acer Veriton X2660g. Sadly, the Dell Vostro 3900 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
Having a Power Supply Unit with high power rating is important, if you are going to use components which require extra power. The Acer Veriton X2660g comes with a decent 250 Watt PSU, but the Dell Vostro 3900 has a more powerful one rated at 300 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.