Dell Inspiron 3668 vs. Dell OptiPlex 7040 SFF
Comparison and Differences
Differences between Dell Inspiron 3668 and Dell OptiPlex 7040 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 7040 SFF is older and entered production in 2015.
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 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
The Dell OptiPlex 7040 SFF has 4 RAM slots while the Dell Inspiron 3668 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 Dell Inspiron 3668 is using the faster 2400 MT/s RAM. The Dell OptiPlex 7040 SFF is slower by supporting RAM speeds of up to 2133 MT/s. Additionally, if you will be needing a lot of RAM, better go for the Dell OptiPlex 7040 SFF as it has the ability to run 64 GB of RAM. The Dell Inspiron 3668 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 Dell OptiPlex 7040 SFF has 10 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 7040 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 7040 SFF has 3 slot(s).
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 Dell OptiPlex 7040 SFF. Sadly, the Dell Inspiron 3668 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 Dell OptiPlex 7040 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.
Motherboard
