The vray materials in the viewports (hardware shading) look awful, like they are only 20x20 pixels wide. They render fine, and maya or mental ray textures look fine, but the vray materials look so blurry I can’t place UVs correctly. Anyone else having this issue?
-Gabe
convert them to power of 2 textures, for example 16x16 or 32x32 and see if it persists
This worked for me. From private message:
Hi, I was beta tester of Vray for Maya but din’t manage to gather money to buy it so I am unable to post on that part of forum. I am providing you answer over PMB so you can post it in forum if you want and if it fixes you problem.
When you apply texture Vray or Maya create quick snapshot of it and apply low quality image for preview purposes. You can open UV texture editor, and from Image menu choose next image in row which should be better quality one.
Hope this helps.
Best,
SreckoM
In Maya 2009 it is the Textures menu in the UV editor. The power of 2 texture (tried 512) didn’t work.
I have this issue to but I don’t really understand the solution SreckoM posted. 
Assign your shader to an object,
select the object and open up the UV editor,
in the UV editor there is a menu named “Textures”
select your file node under that menu and you should get a good quality image in your viewport.
Srecko mentioned the “Image” menu, so maybe it is in a different place in other versions of Maya.
Thank you for explaining this, I’ll take a look at it.