Does it overheat with three monitors? Have an x220 (older notebook but with 16gb and SSD) and it is impossible to use it with two external 1080p monitors without cpu throttling.
Use https://www.hwinfo.com/ it will show you the CPU multiplier, if you experience throttling the multiplier will be low and never go up. Look at the following picture: http://cdn.ultrabookreview.com/wp-content/uploads/2014/03/hw...