My pc is an HP z200 with intel I3 3 ghz and 4 ram and Windows XP

About 1 time a week SW 2011 would lock up and cause me to restart.

I just loaded 2012 and things seem to be working slower.

My 3d mouse seeems slow and jerky and moving assemblies takes longer then normal.

I noticed this is the last year for Windows XP.

Could XP with SW 2012 be creating issues or could my pc be too slow for 2012?