Unfortunately the last update to Arduino IDE 1.6.8 caused a couple of issues:
- "ld returned 5 exit status" when compiling, making it impossible to get working bytecode
- 100% CPU usage by services.exe and java.exe (or javaw.exe) even when the IDE is idle
But I found no solution (and nobody complaining either) to the second issue, so I am reverting back to 1.6.5 that, as far as I remember, had no problems. Otherwise I will go backwards with releases until I reach a stable point again.
Edit: yes, 1.6.5r5 does work indeed. It is a Windows XP SP3 with a Intel centrino CPU.