Because it is difficult to see this clip with. Lenovo ThinkCentre M83 Business Class Gaming Desktop - Quad Core i7 Ghz, 16GB DDR3 RAM, GB SSD, NVIDIA GT 4GB DDR5, teclado, mouse, WiFi. PCI Express card slots come with a clip that needs to be pulled back in order to release the card. Lenovo ThinkCentre M83 Business Class Fast Gaming Desktop Core i7 Ghz, 16 GB de RAM, GB SSD, NVIDIA GT 4GB DDR5, teclado, mouse, WiFi. However, the PC claims it can't find an OS on startup. I recently installed a PCIe SSD to my ThinkCentre M83 and installed Linux on it. .