Sometimes older stuff is better built:
ASUS Maximus IV Extreme is a bit pricy , it uses 8 phase digital VRM with DirectFETs (basically similar to PowIRstage this integrates the driver mosfet + high+low side mosfets for higher efficiency and better VRM temps)
ASUS Maximus IV Z68 Gene-Z is solid if you can deal with microatx : 8 phase digital VRM unlike the Maximus V Z77 Formula/Gene stuff
* Z68 Gene-Z http://www.techpowerup.com/reviews/ASUS/Maximus_IV_Gene-Z/12.html
* Z68 Gene-Z http://www.hardocp.com/article/2011/09/24/asus_maximus_iv_genez/7#.UeCfXG2RXDA
AsRock P67/ Z68 Extreme4 = 8 phase digital VRM , although the P67 one has better capacitors, inductors and NXP LFPAK MOSFETs ... note the Z77 Extreme4 is pretty bad , analog 4 phase VRM with D-PAK mosfets .
* Z68 http://www.pctreiber.net/2011/asrock-z68-extreme4.html/5#pct-check-stabilitaet-kompatibilitaet-alltagserfahrungen
* Z68 http://hardwareoverclock.com/ASRock_Z68_Extreme4_Mainboard-8.htm
I wouldn't go with Gigabyte unless you're going for a Z77 / Z87 board (in which they're better than both ASUS and AsRock then).
Check out http://sinhardware.com/index.php/vrm-listEdited by AlphaC - 7/12/13 at 5:34pm