My laptop is a Dell Vostro 15-3568, using a Core i5-72000U @2.50GHz processor, 4GB RAM and 2 VGA: one is an onboard VGA, Intel HD Graphics 620, another one is AMD Radeon R5 M420. I want to upgrade that AMD graphics card to at least a GeForce GTX 760-class (2GB) and upgrade the RAM to 8GB. So is it possible to upgrade that graphics card on my laptop? When I bought it, the dealer said that I can upgrade it, but I'm not so sure about that.