PC foir blender need advice

Hi, I´ve been searching a PC for a time, and next Monday In my country a shop makes considerable discounts in Computers. So I´ve decided to buy definitively a PC almost only for blender and video edition and postprocessing.
I´ve three in my sight.

a)http://tiendas.mediamarkt.es/p/pc-gaming-acer-predator-g3-605-i7-4770-16gb-nvidia-gt-4gb-1233868

b)http://tiendas.mediamarkt.es/p/pc-gaming-medion-pc8950-i7-4770-ram-16gb-2tb-128gb-ssd-nvidia-geforce-gtx760-1225824

c)http://tiendas.mediamarkt.es/p/pc-gaming-medion-pcb064-i7-4770k-ram-16gb-2tb-128gb-ssd-nvidia-geforce-gtx760-1231218#prodinfotabdesc

In graphic cards, a) seems to have a a Nvidia gtx serie 6, with 4gb, b) gtx760 PCI express1,5gb and c)gtx760 1,5gb.

I´ll like your advice in two points:
a)Which one will you choose atending only to performance…(three of them fits my budget).
b)Will it be worth to install in a medium term time, a second graphic card to work in parallel at b and c?.

Thanks and kind regards.

Can anyone help me please with your opinions or advice? Tomorrow is the day and I haven´t a clear choice.

Is 1,5gb very little vram? Is better a 760 than a 750? Is PCI Express impòrtant? Will it be worth in a future to buy a second Graphic card if the first one has only 1,5gbVram? Wich will you buy?

Thanks in advance for your help and comments.
Kind regards…

Hey.
I think I would choose C of these three. It’s a bit cheaper than B, but i cant see much of a difference in specs? Other than the C has the 4770K CPU so you might be able overclock a bit later on if you want to.

1.5GB of Vram isnt much for cycles no. But you can start out with that, and then add a second graphics card later with more vRAM. Just be sure that the motherboards on the those computers support dual GPU and that the PSU is big enough to handle it.