Can't help you with efficiency. I just hooked up the old HD and copied my files over to the new one. I was also running the 32 bit version of Windows, and wanted to finally make the jump to a 64 bit version. I bought a clean (full, not upgrade) 64 bit copy directly from Microsoft on a flash drive. I should have made that switch when it was first available, but later upgrades wouldn't allow me to switch to the 64 bit version. I did a completely clean upgrade with a new copy of Windows...new SDD, new 64 bit copy of Windows, a fresh clean start. Recommend anyone still running a 32 bit version of Windows on a HDD to do both upgrades on their next computer build. You can always hook your old HD as a secondary drive, so make sure your boot order is correct.