Dell OptiPlex 980 DT vs. Dell OptiPlex 990 MT

Comparison and Differences

Dell_OptiPlex_980_DT.jpg case front and back pannelDell_OptiPlex_990_MT.jpg case front and back pannel
Model
Form factorDesktopMini Tower
CPU optionsIntel Gen1 i3/i5/i7; Pentium Dual Core;Intel Gen2 i3/i5/i7; Celeron; Pentium;
ChipsetQ57 Q67
Dedicated GPU *GeForce GTX 1650 Low ProfileGeForce GTX 1650
RAMDIMM DDR3-1060/1333DIMM DDR3-1333
RAM slots44
RAM speed1333 MT/s1333 MT/s
RAM max16 GB16 GB
USB ports(8x)USB-A 2.0; (10x)USB-A 2.0;
Video portsDisplayPort 1.2; VGA;DisplayPort 1.2; VGA;
Other portsRJ45; Hdph; (2x) Mic; Line-Out; Line-In; PS2/COM; Serial; Parallel; eSATARJ45; Hdph; (2x) Mic; Line-Out; Line-In; PS2/COM; Serial;
Optional portsN.A.Parallel
SATA ports44
PCI slotsPCIe 2.0 x16; PCIe 2.0 x4;PCIe 2.0 x16; PCIe 2.0 x4; PCIe 2.0 x1;
M.2 slotsN.A.N.A.
Drive bays(2x)3.5in; 5.25in;(2x) 3.5in; (2x) 2.5in; (2x) 5.25in;
PSU255 W265 W
Weight8.30 kg (18.29 lb)8.87 kg (19.55 lb)
Released20102011
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 980 DT and Dell OptiPlex 990 MT

If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 990 MT which was released in 2011. The Dell OptiPlex 980 DT is older and entered production in 2010.

If you are looking for the smaller form factor the Dell OptiPlex 980 DT is the right one for you. It is smaller than the Dell OptiPlex 990 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 990 MT as it is running a newer generation CPU. This is not to say that Dell OptiPlex 980 DT is bad - it can still run some powerful CPUs, albeit being an older generation.

Memory

Both models have have equal amount of ram slots (4 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.

None of the desktops has an advantage when it comes to the speed of the RAM being used. Both models support RAM speeds of up to 1333. 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 MT has 10 USB ports. The Dell OptiPlex 980 DT 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.

None of the models has an HDMI port. If your monitor supports only the HDMI interface, you will need to buy an adapter. Such adapters are cheap so nothing to worry about.

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.

M.2 SSD interface allows you to transfer data with higher speeds compared to the old SATA interface. Unfortunately, neither the Dell OptiPlex 980 DT, nor the Dell OptiPlex 990 MT 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 980 DT comes with a decent 255 Watt PSU, but the Dell OptiPlex 990 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_OptiPlex_980_DT_motherboard.jpg motherboard layoutDell_OptiPlex_990_MT_motherboard.jpg motherboard layout