@egs I think that the VGA in 3593 and 5593 is wrong. Went through many web searches and found only the MX 230 comes for these models and not the MX 250 as stated above. Please confirm whether this is true.
Yes what you have indicated is correct, we checked the dell site and it indicates MX230 for both models. At the same time Inspiron 5593 VGA is only 2GB however the distributor has indicated as 4GB in them. We will check and update you.