11-20-2015 05:45 PM
Good day and welcome to the community.
As with most every laptop, the graphics subsystem is either integrated with the CPU package, or if it's an actual discrete GPU, soldered to the system board. In some cases a particular machine may have been offered with either integrated or discrete graphics. In that instance, a machine with integrated graphics might be upgraded via a system board swap.
Looking at pg2 of the L440 FRU Parts List: https://download.lenovo.com/parts/ThinkPad/l440_fru_list_20140825.pdf
you'll see main two types of system boards. One is "Integrated Graphics 4600" and the other is "nVdia N14M-GE with 1GB", so you do have that option, but it could be costly.
You can refer to the hardware manual: https://download.lenovo.com/ibmdl/pub/pc/pccbbs/mobiles_pdf/l440_l540_hmm_en_sp40a26004_03.pdf
to get an idea of the physical task.
Hope this helps to clarify.