No upgrade necessary.
Not sure if your long boot times are before or after the Windows screen appears, but Asus TPU could be culprit getting to the Windows screen since TPU may be doing some OC stability checks on boot. TPU is a great tool to discover what OC your system is capable of, but after that first boot, I'd just jot down the settings TPU is applying, turn TPU off, and manually OC to your liking.
Other things to look for
Do you have quick boot enabled?
Have you turned off unused controllers in the BIOS (Serial port for example). The less things the mobo has to check for the quicker it boots to Windows.
Do you have your SSD at the top of the list in boot priority? If the mobo is checking for flash and optical drives with bootable media inserted, that can take longer.
Once you get to the Windows screen, the motherboard has very little to do with boot times. For all practical purposes, it's done with it's duties by that time.
Main: i5-3570K, ASRock Z77 Pro4-M, MSI RX480 8G, 500GB Crucial BX100, 2 TB Samsung EcoGreen F4, 16GB 1600MHz G.Skill @1.25V, EVGA 550-G2, Silverstone PS07B
HTPC: A8-5600K, MSI FM2-A75IA-E53, 4TB Seagate SSHD, 8GB 1866MHz G.Skill, Crosley D-25 Case Mod