1. Get lots of RAM.
2. Have a GPU with plenty of memory, 512 MB+.
3. (Optional) Ramdisk your WoW data folder, and symlink to it from your install dir. 1-2 GB/s and practically near-zero access time should help load times.

However, it's also possible that on loading textures, some modulation and whatnot takes place in CPU/memory, which can basically only be alleviated by having more CPU power. Quad core and high speeds is your friend.

I'm running a Core2Quad at 3.0 GHz, 4 GB mem, 768 MB card. Only occasionally do I have load stutter in Shatt and AV.


By the way, the 3.0 GHz is a 2.4 GHz Q6600 auto-overclocked by the motherboard.. stock cooling, lol.. I guess it will blow up soon.




Edit: I suppose having a "killer nic" could reduce your latency by a small amount... which could be useful.. but like Fursphere indicates, your current problem does not lie with NIC performance.