Dell OptiPlex 3000 Tower vs. Lenovo ThinkCentre M900 Small

Comparison and Differences

Dell_OptiPlex_3000_Tower.jpg case front and back pannel

Lenovo_ThinkCentre_M900_Small.jpg case front and back pannel

Model
Form factor	Mini Tower	Small
CPU options	Intel Gen 12 i3/i5/i7/i9; Pentium	Intel Gen6 i3/i5/i7; Celeron; Pentium;
Chipset	B660	Q170
Dedicated GPU *	GeForce GTX 1650 Super	GeForce GT 1030 Low Profile
RAM	DIMM DDR4-3200	DIMM DDR4-2133
RAM slots	2	4
RAM speed	3200 MT/s	2133 MT/s
RAM max	64 GB	64 GB
USB ports	(4x) USB-A 2.0; (4x) USB-A 3.0;	(8x)USB-A 3.0;
Video ports	Display Port 1.4a; HDMI 1.4b;	(2x) DisplayPort 1.2; VGA;
Other ports	RJ45; Audio; Line-Out/In;	RJ45; Hdph; (2x) Mic; Line-Out; Line-In; Serial;
Optional ports	HDMI 2.0b/Displayport/VGA; Serial	2x USB-A 2.0; Media card reader (USB 2.0); (2x) PS2; eSATA;
SATA ports	3	3
PCI slots	PCIe 3.0 x16; (2x) PCIe 3.0 x1;	PCIe 3.0 x16; PCIe 3.0 x1; PCIe 3.0 x16 (wired x4); M2 to PCI adapter (optional);
M.2 slots	M.2 2230/2280 (PCIe 4.0 x4, NVMe); M.2 2230 (WiFi/BT)	M.2 (WiFi/BT or PCI extension card)
Drive bays	3.5in; (2x) 2.5in; 5.25in (slim);	2.5in; 2.5/3.5in; 5.25in (slim);
PSU	180/240/300 W	TFX 210 W
Weight	6.61 kg (14.59 lb)	9 kg (19.8 lbs)
Released	2022	2015
Manual	link	link
Price**	Check Price	Check Price

** As an Amazon associate we earn from qualifying purchases.
* 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 3000 Tower and Lenovo ThinkCentre M900 Small

If you are looking for a more modern desktop, then you should go with the Dell OptiPlex 3000 Tower which was released in 2022. The Lenovo ThinkCentre M900 Small is older and entered production in 2015.

If you are looking for the smaller form factor the Lenovo ThinkCentre M900 Small is the right one for you. It is smaller than the Dell OptiPlex 3000 Tower 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 3000 Tower as it is running a newer generation CPU. This is not to say that Lenovo ThinkCentre M900 Small is bad - it can still run some powerful CPUs, albeit being an older generation.

Memory

The Lenovo ThinkCentre M900 Small has 4 RAM slots while the Dell OptiPlex 3000 Tower 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 3000 Tower is using the faster 3200 MT/s RAM. The Lenovo ThinkCentre M900 Small is slower by supporting RAM speeds of up to 2133 MT/s. In addition, you will be able to install the same amount of RAM in both models, and most probably 64 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

Both models have the same amount of USB ports for total count of 8. If this is not enough, using a USB hub is always a viable option. 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.

DisplayPort is crucial for any desktop machine. It is good to see that both models are featuring DisplayPorts. However, the Lenovo ThinkCentre M900 Small comes with 2 ports, while the Dell OptiPlex 3000 Tower has only 1. If you are planning to use multiple monitors, the Lenovo ThinkCentre M900 Small is the better choice.

The Dell OptiPlex 3000 Tower comes with an HDMI port, while the Lenovo ThinkCentre M900 Small 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.

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 3000 Tower. Sadly, the Lenovo ThinkCentre M900 Small 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 Lenovo ThinkCentre M900 Small comes with a decent 210 Watt PSU, but the Dell OptiPlex 3000 Tower has a more powerful one rated at 300 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.