I have recently installed android studio and all its update using sdks manager. When i try to start the emulator i can see this:
emulator -netdelay no
Also look at your skins - some have found it works with the WVGA800 skin. Others here have found it's due to the high RAM requirements of the Nexus 5 AVD itself. I think Nexus 5 takes almost 1600. Try either decreasing the RAM allocation in the AVD ('Advanced settings') - or reinstall HAXM with a higher RAM limit.