introduced a new style of cases, made with recyclable plastics. The first two models, namely the 960 and 980 were based on BTX, However the rest of this series was built upon the standard ATX and DTX. From the x020 and onwards, Dell switched over from a standard 24 pin power connector to a proprietary 12v only 8 pin connector for better power efficiency. The DT and SSF models from this series used standard TFX and LFX power supplies, respectively (the LFX power supplies do have a nonstandard depth of 240mm, however), while the MT models used standard ATX power supplies. Series 5 Dell OptiPlex computers sold from 2015 to 2020 use cases that resembled the style used in Dell laptops of the same era. These OptiPlex machines are no longer standard ATX or MicroATX. Windows 11 support Windows 11 requires TPM 2.0 and an 8th generation Intel or newer processor. Some models in Series 5 between 2015 and 2019 shipped with TPM 1.2, but are capable of meeting these requirements with a firmware upgrade to TPM 2.0 and the appropriate minimum CPU. Potential models that may be able to support Windows 11 include: Intel H370 chipset (3060 / 3070), Intel Q370 chipset (5060 / 5070, 5260 / 5270, 7060 / 7070 / 7070 Ultra, 7460 / 7470, 7760 / 7770). Series 6 - Pro 2 The Dell OptiPlex chassis now follows the Pro 2 chassis introduced with the OptiPlex 7071 and now also on the 3080, 5080 and 7080 models. Up to a 500W 92% 80+ Platinum PSU and support for Nvidia RTX Graphics Cards. All Models including All-in-ones offer 802.11ax WiFi 6 Options and all Desktop models offer a Serial Port Adapter, which can be expanded with a variety of ports including; Serial Ports, VGA, DisplayPorts, HDMI, and USB Type C alt DisplayPorts. OptiPlex offers Energy Star 8.0 configurations, as well as EPEAT Silver and Gold configurations to its customers. Models, in relative chronological order Series 1 Series 2 (Midnight grey) Series 3 (BTX) Series 4 Series 5 Series 6 OptiPlex XE The Dell OptiPlex XE is a special version designed for equipment manufacturer, retail/point-of-sale (POS) systems. They are based on the standard OptiPlex models with added features; such as a higher heat threshold, MIL-STD 810G testing and powered USB/Serial. Notes See also HP business desktops Dell Latitude and Precision Lenovo ThinkCentre and ThinkStation desktops Fujitsu Esprimo References