Just got back from a long trip and wanted to play some minecraft. Grabbed a '1.8 ready' texture pack, changed my game version to 'latest snapshot', and ran it. Went to the options menu to enable the texture pack, and it lags like nothing I've ever seen. I can't even get to the resource options it lags so bad. The menu lag is present for every game version past 1.7.9. Everything before that works just fine.
While I was away from home I played the snapshots on my friend's computer and it was fine, any ideas why it's not working for my computer?