Did you notice that all six of those SATA ports are connected to the Intel SATA controller on the Intel P67 Express chipset?
That looks like a picture of the Z68 Extreme7 Gen3 to me not a P67 Extreme4 Gen3.
The four SATA connectors to the right of the sticker are connected to the ASMedia ASM1061 SATA3 controller.
If you really do have a P67 Extreme4 Gen3 then the two SATA connectors to the right of the sticker are connected to the Marvell SE9120 SATA3 controller.
The non-Intel SATA controllers are known to be slower than Intel's SATA controller. The scan for attached SATA devices on the non-Intel SATA controller(s) happens after the scan on the Intel SATA controller hence the reason for the longer boot time.