Dell OptiPlex 3090 SFF vs. Dell Pro Tower Plus QBT1250
Comparison and Differences
Differences between Dell OptiPlex 3090 SFF and Dell Pro Tower Plus QBT1250
If you are looking for a more modern desktop, then you should go with the Dell Pro Tower Plus QBT1250 which was released in 2025. The Dell OptiPlex 3090 SFF is older and entered production in 2021.
If you are looking for the smaller form factor the Dell OptiPlex 3090 SFF is the right one for you. It is smaller than the Dell Pro Tower Plus QBT1250 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 Pro Tower Plus QBT1250 as it is running a newer generation CPU. This is not to say that Dell OptiPlex 3090 SFF is bad - it can still run some powerful CPUs, albeit being an older generation.
Memory
The Dell Pro Tower Plus QBT1250 has 4 RAM slots while the Dell OptiPlex 3090 SFF 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 Pro Tower Plus QBT1250 is using the faster 5600 MT/s RAM. The Dell OptiPlex 3090 SFF is slower by supporting RAM speeds of up to 2666 MT/s. Additionally, if you will be needing a lot of RAM, better go for the Dell Pro Tower Plus QBT1250 as it has the ability to run 128 GB of RAM. The Dell OptiPlex 3090 SFF can do a bit less at max 64 GB. Most of the times, this should be sufficient for the majority of users.
Ports
In total the Dell Pro Tower Plus QBT1250 has 10 USB ports. The Dell OptiPlex 3090 SFF 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. What is nice about the Dell Pro Tower Plus QBT1250, is that it has 2 USB 3.1 port(s) which allows transfer of up to 10Gb/s. Unfortunately, the Dell OptiPlex 3090 SFF has no such port, thus restricting your transfer speeds significantly. For people who want to use external drives on regular basis, this might be an issue.
DisplayPort is crucial for any desktop machine. It is good to see that both models are featuring DisplayPorts. However, the Dell Pro Tower Plus QBT1250 comes with 3 ports, while the Dell OptiPlex 3090 SFF has only 2. If you are planning to use multiple monitors, the Dell Pro Tower Plus QBT1250 is the better choice.
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 2 SATA slot(s). Keep in mind that having too few SATA slots might limit your options for connecting additional memory drives.
An M.2 SSD can be several times faster than a SATA one. Thus, we are happy to see that both models support the M.2 interface. However, the Dell Pro Tower Plus QBT1250 has 1 M.2 slots while the Dell OptiPlex 3090 SFF comes with just 1.
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 3090 SFF comes with a decent 200 Watt PSU, but the Dell Pro Tower Plus QBT1250 has a more powerful one rated at 360 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
