Dell Inspiron 3668 vs. Dell OptiPlex 790 MT

Comparison and Differences

Dell_Inspiron_3668.jpg case front and back pannelDell_OptiPlex_790_MT.jpg case front and back pannel
Model
Form factorMini TowerMini Tower
CPU optionsIntel Gen6 i3/i5/i7; Celeron; Pentium;Intel Gen2 i3/i5/i7; Celeron; Pentium;
ChipsetH110Q65
Dedicated GPU *GeForce GTX 1650 SuperGeForce GTX 1650
RAMDIMM DDR4-2133/2400DIMM DDR3-1333
RAM slots24
RAM speed2400 MT/s1333 MT/s
RAM max16 GB16 GB
USB ports(2x) USB-A 3.0; (4x) USB-A 2.0;(10x)USB-A 2.0;
Video portsHDMI 1.2; VGA;DisplayPort 1.2; VGA;
Other portsRJ45; Hdph; Mic; Line-Out; Line-In; Card Reader;RJ45; Hdph; (2x) Mic; Line-Out; Line-In; PS2/COM; Serial;
Optional portsN.A.Parallel
SATA ports54
PCI slotsPCIe 2.0 x16; (2x) PCIe 2.0 x1;PCIe 2.0 x16; PCIe 2.0 x4; PCIe 2.0 x1;
M.2 slotsM.2 2230 (WiFi/BT)N.A.
Drive bays(2x) 2.5in; 3.25in; 9.5mm(2x) 3.5in; (2x) 2.5in; (2x) 5.25in;
PSU240 W265 W
Weight5.90 kg (13.01 lb)8.87 kg (19.55 lb)
Released20162011
Manuallinklink
Price**Check PriceCheck Price

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* Dedicated GPU warning: Check if your particular power supply model has enough power. Additionally some PSUs don't come with an auxiliary PCIe power connector and you may need to buy a SATA to PCIe power adapter.

Differences between Dell Inspiron 3668 and Dell OptiPlex 790 MT

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 790 MT is older and entered production in 2011.

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 Dell Inspiron 3668 as it is running a newer generation CPU. This is not to say that Dell OptiPlex 790 MT is bad - it can still run some powerful CPUs, albeit being an older generation.

Memory

The Dell OptiPlex 790 MT 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 790 MT is slower by supporting RAM speeds of up to 1333 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 790 MT 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 790 MT 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.

The Dell Inspiron 3668 comes with an HDMI port, while the Dell OptiPlex 790 MT 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 Dell Inspiron 3668 is better equipped as it comes with 5 SATA slot(s), while the Dell OptiPlex 790 MT has 4 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 790 MT, 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 Inspiron 3668 comes with a decent 240 Watt PSU, but the Dell OptiPlex 790 MT has a more powerful one rated at 265 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

Dell_Inspiron_3668_motherboard.jpg motherboard layoutDell_OptiPlex_790_MT_motherboard.jpg motherboard layout