Dell OptiPlex 990 SFF case front and back pannel

Dell OptiPlex 990 SFF

Specification and Upgrade Options

The Dell OptiPlex 990 SFF is a pre-built business desktop computer first released in 2011. Although more than five years old, it is still a viable solution for home and office. The motherboard is using the Q67 chipset and supports 2th gen Intel Core processor, 16GB of DIMM DDR3-1333 memory, and a low profile GPU. You can even make a gaming PC form this machine with a proper GPU upgrade.

Dell OptiPlex 990 SFF is a Small form factor computer. The Small Form Factor (SFF) is an in-between model. It has less space for the larger form factors (Mid tower, Mini tower, and Desktop), but it is still easily upgradable. Usually the SFF come with 2x PCIe slots, so fitting a low profile graphics card is possible.

Specification

Model
Form factorSmall
CPU optionsIntel Gen2 i3/i5/i7; Celeron; Pentium;
ChipsetQ67
Dedicated GPU *GeForce GTX 1650 Low Profile
RAMDIMM DDR3-1333
RAM slots4
RAM speed1333 MT/s
RAM max16 GB
USB ports(10x)USB-A 2.0;
Video portsDisplayPort 1.2; VGA;
Other portsRJ45; Hdph; (2x) Mic; Line-Out; Line-In; PS2/COM; Serial; Parallel;
Optional portsN.A.
SATA ports3
PCI slotsPCIe 2.0 x16; PCIe 2.0 x4; PCIe 2.0 x1;
M.2 slotsN.A.
Drive bays3.5in; 2.5in; 5.25in(slim);
PSU240 W
Weight5.70 kg (12.57 lb)
Released2011
Manuallink
Price**Check Price

* 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.
** As an Amazon associate we earn from qualifying purchases.

Windows 11 compatibility

No, Dell OptiPlex 990 SFF does not meet the Windows 11 hardware requirements. According to Windows 11 specification, all models with Intel 7th Gen CPU or older are not officially supported. Processor with TPM 2.0 and a UEFI Secure boot BIOS is also required in order to upgrade from Windows 10 to Windows 11 through Windows Update.

However, anyone with PC that does not pass the upgrade test can download the official Windows 11 ISO, make a bootable flash drive, and install the OS manually.

Processor

The Dell OptiPlex 990 SFF supports Gen2 Intel Core technology. Intel introduced their second generation micro architecture named Sandy Bridge in 2011. The maximum number of cores is 6 (on an i7 processor). Desktops use the 1155 LGA socket and DDR3-1066 RAM. The second generation of Intel Core is old but still sufficient for office, home tasks and retro gaming. If you plan to enjoy more recent games, a more recent CPU is required.

Best CPUs for Dell OptiPlex 990 SFF upgrade:

Model Cores (Threads) Base frequency Turbo
Core i5 2500 4(8) 3.3 GHz 3.7 GHz
Core i7 2600 4(8) 3.4 GHz 3.8 GHz
Core i7 2700K 4(8) 3.5 GHz 3.9 GHz

Memory

Dell OptiPlex 990 SFF has four RAM slots and supports dual channel memory configuration. This is sufficient for almost any use case and especially in situations where the workload calls for more RAM.

To cover the needs of your OS, games, and apps, Dell OptiPlex 990 SFF supports up to 16 GB of DIMM DDR3-1333 RAM. For office work, home use, and light gaming we recommend 8GB of RAM. For everything else, use 16GB or more.

Faster RAM speeds permit your processor to access the data stored inside the memory faster. This is important for the overall speed of your system. The motherboard of the Dell OptiPlex 990 SFF supports RAM speeds of up to 1333 MT/s.

Wi-Fi Support

Dell OptiPlex 990 SFF doesn't come with any on-board Wi-Fi support. In that case, you have two options to upgrade this model with Wi-Fi. You either use an external USB Wi-Fi adapter (wireless network dongle) or a PCIe-based wireless adapter.

The USB dongle is much more convenient and easy to install, but has less space for a decent antenna and can have thermal problems. On the other hand, the PCIe based adapter is much more powerful, more reliable, and has better antenna, but it is harder to install.

Best Wireless adapters for Dell OptiPlex 990 SFF:

Model Speed Frequency Interface
WiFi 6E (Gig+) Kit 3000 Mbit/s 2.4GHz / 5GHz NGFF M.2 A/E Key
Rekong AX210 3000 Mbit/s 2.4GHz / 5GHz NGFF M.2 A/E Key
Gigabyte GC-Wbax200 2400 Mbit/s 2.4GHz / 5GHz PCIe
TP-Link Archer TX50E 2400 Mbit/s 2.4GHz / 5GHz PCIe
TP-Link Archer T9UH 1300 Mbit/s 2.4GHz / 5GHz USB 3.0

Ports

Ports are important and often people don't think about them when buying a PC. For example, if you don't have enough USB ports, using external devices becomes problematic. Before you buy any system, considering your use case, check the number of external devices you are going to use and plan the number of the extension ports accordingly.

USB ports

The Dell OptiPlex 990 SFF comes with ten USB ports in total. Having more USB ports is always better, but also pay attention to the version of those USB ports. Higher version ports support faster transfer speeds. Unfortunately, this model doesn't come with a USB 3.1 port. If you need a faster connection for your peripherals, like external Solid State Drive, you will need to choose another model.

Video ports

The DisplayPort (DP) is the most widely used digital interface for transmitting digital video and audio between display devices and PCs. It is good to see that the Dell OptiPlex 990 SFF is featuring a DisplayPort 1.2. The post version is important if you target higher resolutions with high refresh rate. Although, ver. 1.2 is completely fine for most users, if possible, aim for the higher versions DisplayPort.

The HDMI port is another digital video port you can use to connect external display. It has very similar capabilities to the DisplayPort with few exceptions. However, the Dell OptiPlex 990 SFF doesn't have one. This is not a problem if there is on-board DisplayPort.

*Please keep in mind in order to use the video ports available through the motherboard, you need a CPU with integrated graphics card. If you have a dedicated GPU, use his ports instead.

SSD storage - M.2 sockets and SATA ports

The SATA port is one of the places where you can connect a stora gedevice. The Dell OptiPlex 990 SFF comes with three SATA port(s). Not enough SATA ports might limit your options for additional storage devices. Think about your use case and decide if the SATA ports provided by this model will be sufficient.

Unfortunately, the Dell OptiPlex 990 SFF has no M.2 PCIe soket and you have to rely on the available SATA ports to connect your drives.

The M.2 PCIe SSD connector in combination with an NVMe drive allows for higher transfer rates, compared to the old SATA interface. In some situations, NVMe device connected to the M.2 PCIe socket can be more than 5 times faster.

Power Supply

The Dell OptiPlex 990 SFF comes with a 240 Watt PSU. Having a power supply with high power rating is important, especially if you are doing upgrade with addtional components, like dedicated GPU and more HDDs. Will this 240 W be enough, it all depends on your specific use. Please keep in mind that some models might have more than one PSU option. Whenever possible get the most powerful one, as it might make future upgrades easier.

Motherboard

Dell_OptiPlex_990_SFF_motherboard.jpg motherboard layout