I had to switch comps and re-install photoshop and now my icons look like *insert negative word here*. How do I fix this?

Before I switched:
After:
I used the same technique for BOTH icons, yet the after is so grainy, no?


It's on RGB and 16 bit, and it still looked terrible on 8 bit. Does anyone see what I'm talking about and know how to fix it?



*promises tutorial once it's fixed to make up for annoying questions*