Dell Inspiron 3668 vs. Dell OptiPlex 3040 SFF
Comparison and Differences
Differences between Dell Inspiron 3668 and Dell OptiPlex 3040 SFF
If you are looking for a more modern desktop, then you should go with the Dell Inspiron 3668 which was released in 2016. The Dell OptiPlex 3040 SFF is older and entered production in 2015.
If you are looking for the smaller form factor the Dell OptiPlex 3040 SFF is the right one for you. It is smaller than the Dell Inspiron 3668 and will fit more easily under your desk.
Processor
The two models have the same generation of Intel processors. We think that the 6 generation of Intel Processors have enough power to execute all of the home and office tasks that most people will care to do.
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 Inspiron 3668 is using the faster 2400 MT/s RAM. The Dell OptiPlex 3040 SFF is slower by supporting RAM speeds of up to 1600 MT/s. In addition, you will be able to install the same amount of RAM in both models, and most probably 16 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 Dell OptiPlex 3040 SFF has 8 USB ports. The Dell Inspiron 3668 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 3040 SFF has a DisplayPort. The Dell Inspiron 3668 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 Dell Inspiron 3668 is better equipped as it comes with 5 SATA slot(s), while the Dell OptiPlex 3040 SFF has 2 slot(s).
M.2 SSD interface allows you to transfer data with higher speeds compared to the old SATA interface. Unfortunately, neither the Dell OptiPlex 3040 SFF, nor the Dell Inspiron 3668 has one. However, you can still use a SATA SSD drive which should give you satisfactory performance.
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 3040 SFF comes with a decent 180 Watt PSU, but the Dell Inspiron 3668 has a more powerful one rated at 240 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.