Dell OptiPlex 7040 SFF vs. Lenovo ThinkCentre M900 Tower

Comparison and Differences

Dell_OptiPlex_7040_SFF.jpg case front and back pannelLenovo_ThinkCentre_M900_Tower.jpg case front and back pannel
Model
Form factorSmallMini Tower
CPU optionsIntel Gen6 i3/i5/i7Intel Gen6 i3/i5/i7; Celeron; Pentium;
ChipsetQ170Q170
Dedicated GPU *GeForce GT 1030 Low ProfileGeForce GTX 1660 Super
RAMDIMM DDR4-2133 DIMM DDR4-2133
RAM slots44
RAM speed2133 MT/s2133 MT/s
RAM max64 GB64 GB
USB ports(6x) USB-A 3.0; (4x) USB-A 2.0; (8x)USB-A 3.0;
Video ports(2x) Display Port 1.2; HDMI 1.4;(2x) DisplayPort 1.2; VGA;
Other portsSerial; (2x) PS2; RJ45; Headset; Line-Out; RJ45; Hdph; (2x) Mic; Line-Out; Line-In; Serial;
Optional portsVGA; Media Card Reader;2x USB-A 2.0; Media card reader (USB 2.0); (2x) PS2; eSATA;
SATA ports33
PCI slotsPCIe 3.0 x16; PCIe 3.0 x4;PCIe 3.0 x16; PCIe 3.0 x1; PCIe 3.0 x16 (wired x4); M2 to PCI adapter (optional);
M.2 slotsM.2 2280 M-key (PCIe 3.0 x4, NVMe) M.2 (WiFi/BT or PCI extension card)
Drive bays3.5in/(2x)2.5in; 5.25in (slim); (2x) 2.5/3.5in; (2x) 5.25in;
PSU180 WATX 250/400 W
Weight6.00 kg (13.22 lb)12.5 kg (27.5 lb)
Released20152015
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 7040 SFF and Lenovo ThinkCentre M900 Tower

Both computers, the Dell OptiPlex 7040 SFF and the Lenovo ThinkCentre M900 Tower, were released during the same year - 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 Lenovo ThinkCentre M900 Tower 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

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 2133. 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

In total the Dell OptiPlex 7040 SFF has 10 USB ports. The Lenovo ThinkCentre M900 Tower 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 7040 SFF comes with an HDMI port, while the Lenovo ThinkCentre M900 Tower 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 7040 SFF. Sadly, the Lenovo ThinkCentre M900 Tower 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 Lenovo ThinkCentre M900 Tower has a more powerful one rated at 400 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_7040_SFF_motherboard.jpg motherboard layoutLenovo_ThinkCentre_M900_Tower_motherboard.jpg motherboard layout