The notebook comes indeed without an operating system to the customer and because I wanted to install 8.1 DVD from the optical drive from the win, I had the UEFI BIOS with F2 = Biosaufruf first to Legacy, so the old standard switch. This is very important, ignore the talk would be UEFI, this is nonsense !!! Because it was otherwise impossible to come up with the F12 boot menu. : - (( When I was able to boot from the DVD drive, was very quick win 8.1 installed with 64 bits. I have partitioned the hard disk 500 Giga 9GB than vault, because now there are important drivers and programs. Then unfortunately failed the Acer tool that will detect the hardware. It recognized only LAN, but I wanted to Wireless Lan. On the enclosed driver - DVD were two wifi wireless drivers and on my laptop it was Qualcomm Atheros, which was relevant. But this can be different, it will not only Atheros installed. When you're online then, everything goes automatically and quickly ==> praise to Win 8.1! Because I do not like the tiles, I ClassicShell for Win 8.1 installed ==> Hello old Start menu ==> I like you! Now the computer convinced with speed and even more tasks can be opened. This produces surprisingly little heat and the battery life is really close to seven hours. The display is brilliant and radiant - as laughs of progress! Led - Backlight! Prima is the FN control especially for volume and brightness that you need so often. At full brightness even in daylight everything is still visible. Touchpad is ok, but I have connected a USB mouse. A fine instrument, without special frills, obviously an i3 CPU that's going fast, but still stingy deals with the energy. (Waste heat very low, battery life is very high) A gamer laptop, it is not, of course, the graphics card is of the simpler kind. The keyboard has good tactile and pleasant, the number field is a plus! As an electronics technician retired I may say: I am convinced of this product: I can recommend it with a clear conscience! :-))