Upgrading from R9 270x to either Rx470 or Rx480? Motherboard bottlenecks?

[Josephking79]

Hi everyone
Not as simple as the title, at least not for me. After doing much research on these two cards, I'm definitely getting one or the other. The only problem is my motherboard and this ties to my question and a previous thread on the components forum. http://www.tomshardware.com/answers/id-3256993/max-am3-78lmt-s2pt-rev.html
I now have the CPU mentioned but I'm on the fence about the graphics card.

I have this: Socket AM3+ - AMD 760G - GA-78LMT-S2PT (rev. 3.1) http://www.gigabyte.co.nz/products/product-page.aspx?pid=4129&dl=1#dl
I'd like to know, regardless of cost, which would I benefit more from? I know the Rx480 is the better of the two performance wise but is there a chance that it would not reach it's potential in an older motherboard?
My rig:
Motherboard: Socket AM3+ - AMD 760G - GA-78LMT-S2PT (rev. 3.1)
Ram: 8gig (2x4gig of G.Skill) of DDR3 (Part# F3-10666CL9-4GBXL)
CPU: AMD FX-6300
500w psu
Thanks in advance

 

[BradleyJames]

i dont think that older motherboard would bottleneck anything. i dont know if its pci-e 2.0 or 3.0 but ive read up on that and wont make a difference. if u are concerned about it get the cheaper card and a motherboard

 

[herrwizo]

Motherboard won't bottleneck anything. You are free to pick any card as long as it fits within your case and as long as your PSU can handle it. You only mentioned that your PSU is 500W, which tells nothing about quality - what model is it?

 

[Josephking79]

The PSU is a Silverstone, just what I can see from looking through the acrylic window

 

[herrwizo]

They generally make very good PSUs (or at the very least average, so no junk here). You are good to go. If anything, your CPU will sometimes be a bottleneck, it will mostly depend on how much CPU power the particular game needs. Some games chew the CPU power like there is no tomorrow, mostly console ports. But for games that mostly rely on GPU (like Witcher 3), you will be fine.