Dell OptiPlex 3040 MT vs. Dell OptiPlex 990 SFF

Comparison and Differences

Dell_OptiPlex_3040_MT.jpg case front and back pannelDell_OptiPlex_990_SFF.jpg case front and back pannel
Model
Form factorMini TowerSmall
CPU optionsIntel Gen6 i3/i5; Pentium; Celeron; Intel Gen2 i3/i5/i7; Celeron; Pentium;
ChipsetH110Q67
Dedicated GPU *GeForce GTX 1650 SuperGeForce GTX 1650 Low Profile
RAMDIMM DDR3L-1600 DIMM DDR3-1333
RAM slots24
RAM speed1600 MT/s1333 MT/s
RAM max16 GB16 GB
USB ports(4x) USB-A 3.0; (4x) USB-A 2.0; (10x)USB-A 2.0;
Video ports Display Port 1.2; HDMI 1.4;DisplayPort 1.2; VGA;
Other portsRJ45; Headset; Line-Out; RJ45; Hdph; (2x) Mic; Line-Out; Line-In; PS2/COM; Serial; Parallel;
Optional portsSerial+PS2; VGA; Media Card Reader;N.A.
SATA ports33
PCI slotsPCIe 3.0 x16; (3x) PCIe 3.0 x1;PCIe 2.0 x16; PCIe 2.0 x4; PCIe 2.0 x1;
M.2 slotsN.A.N.A.
Drive bays3.5in/5.25in; (2x) 2.5in; 5.25in slim;3.5in; 2.5in; 5.25in(slim);
PSU240 W240 W
Weight7.93 kg (17.49 lb)5.70 kg (12.57 lb)
Released20152011
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 OptiPlex 3040 MT and Dell OptiPlex 990 SFF

If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 3040 MT which was released in 2015. The Dell OptiPlex 990 SFF is older and entered production in 2011.

If you are looking for the smaller form factor the Dell OptiPlex 990 SFF is the right one for you. It is smaller than the Dell OptiPlex 3040 MT 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 Dell OptiPlex 3040 MT as it is running a newer generation CPU. This is not to say that Dell OptiPlex 990 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.

Memory

The Dell OptiPlex 990 SFF has 4 RAM slots while the Dell OptiPlex 3040 MT 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 OptiPlex 3040 MT is using the faster 1600 MT/s RAM. The Dell OptiPlex 990 SFF 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 990 SFF has 10 USB ports. The Dell OptiPlex 3040 MT 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. 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.

The DisplayPort is usually the more popular video port used with desktops and laptops, while the HDMI is used predominantly in consumer electronics. That's why, it is good to see that both of the models come with a DisplayPort.

The Dell OptiPlex 3040 MT comes with an HDMI port, while the Dell OptiPlex 990 SFF 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 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.

M.2 SSD interface allows you to transfer data with higher speeds compared to the old SATA interface. Unfortunately, neither the Dell OptiPlex 3040 MT, nor the Dell OptiPlex 990 SFF 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

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 240 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

Dell_OptiPlex_3040_MT_motherboard.jpg motherboard layoutDell_OptiPlex_990_SFF_motherboard.jpg motherboard layout