The Intel® HD Graphics 5500 are embedded on the 5th generation processors; the system shares the RAM memory with the Intel® HD Graphics. 4th and 5th generation processors share up to 1.7 GB.
There is no dedicated graphics memory unless adding a external(dedicated graphics card); such as Nvidia or ATI.
Now, if you want to set the minimum dedicated graphics memory, you can go to the BIOS and search for Configuration, look for Video and change the IGD Minimun Memory, here is additional information How to Increase Intel HD Graphics Dedicated Video Memory.
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