It should not be a gpu issue i'm running a 1080 you might be right it might be a Maya LT issue

I would normally ask you to send me the scene file but i can't open Maya LT files here, hopefully...

Disconnect the base colour and plug the texture into the colour map box under textures section,

You have use colour map ticked but it looks like colour map under textures is empty.

If it's not...

Just to be clear this is a stingray PBS material on a poly plane only difference is one has the hardware shading turned on in the viewport the other does not!

Hope that maybe helps

I know this might be stating the obvious but you do have hardware texturing turned on right?

It won't show in the viewport if you don't

Did you put MAYA_VP2_WANT_OGS_WARNINGS = 1 in the maya.env file and if so what warnings do you get?

Maybe walk us through the process of whats going wrong, can you access the shaderFX panel? I...