I have one of my PC's set to power up, not wake up, at 3:30pm every day.
I want to change the time to 3:00pm.
I am connected to this PC via Remote Desktop and I'm not able to access the BIOS from here.
Just generally speaking, boot time is directly a function of Windows, and how many things you have loading and running during boot time.
One boot time fix that I apply to every PC that I have to work on, is this:
Shorten the Boot Time in XP, Vista & Windows 7 & 8, 8.1 & Windows 10
Go to the start button, choose run, then type msconfig and press Ok. On the system configuration window, choose the "Boot.INI" tab.
Check “No Gui Boot”, then lower the timeout to a more manageable time. I choose 3 seconds in stead of 30. (windows won’t accept a lower number than 3)
Next choose advanced options. This is where you can choose how many processors you have. Most modern PC's are duo core (2 processors) with some quad core (4 processors, and there are even some with 8 Cores or more, ) then choose OK. The Windows default is only 1 core.
Now choose apply and OK, reboot and you should see a marked decrease in boot time, and an Increase in Run-Time efficiency.
Then you also need to check your Startup files, and only leave starting the things that absolutely, positively MUST start up when you boot up the PC.
I've done everything I can, to speed up the booting of my own PC, where I have an SSD as my C: drive, and my PC boots up in about ten seconds, and shuts down in <5 sec's.
Additional drives, like Flash Drives or CD's can and will also slow down your boot-up.