Recently AlexxLopaztico02 shared a guide on updating to a specific PlayStation 4 Firmware version that may be useful for some users not looking to jump all the way to Sony's current PS4 System Software 4.05 revision. 
Check it out below, to quote: HOW TO: Update to a specific FW on PS4 (Works For Upd 4.0.1)
With the new jailbreak presentation in GeekPwn, the people who are in FW 3.55 would want to update to 4.0.1, without having to update to 4.0.5 and lose to opportunity to jailbreak (ouch)
Lets put clear that this works for ALL the FW, not to the specific 4.0.1, but in this one we gonna update to 4.0.1
Requirements:
0- If you installed a PS4 Update Blocker you'll need to Remove PS4 Update Blocker before you can update your PlayStation 4 Firmware version.
1- First of all, you gotta download the 4.0.1 FW in a PUP file, which you can get clicking this link (mirror here).
Note: if you want another PS4 FW update, check this page (mirror here).
2- Now, format your USB to FAT32 (This will wipe all your data, so make a backup!)
3- Now, make a folder in your flash drive called "PS4" (without the ") Remember it gotta be in UPPER CASE.
4- Inside the PS4 folder, make a folder called "UPDATE" (again without the ") IN UPPER CASE.
5- Copy the file you downloaded at the start of the tut to the UPDATE folder.
6- Rename the file to "PS4UPDATE.PUP"
We're ready in the PC, now lets go to the PS4.
7- First of all, shut down COMPLETELY your PS4.
8- Now, put your finger like if you were turning the console on, but release it when you heard the second beep. In other words: Press and hold the power switch. You will hear one beep, wait until you heard the second beep.
9- Connect the FLASH drive to the PS4, followed act connect via USB the DS4 (Dualshock 4 Controller) and press the PS Button.
10- Select the "Update FW" Option (I think is opt 3) and select via USB drive.
11- Follow the steps on screen, and select "Okay"/"Accept" in everything.
The PS4 Gonna reboot a couple of times, and guess what, you have successfully updated your PS4!
See you next time!
Thanks to @bodeg for letting us know about this tutorial in the PSXHAX Shoutbox!
Check it out below, to quote: HOW TO: Update to a specific FW on PS4 (Works For Upd 4.0.1)
With the new jailbreak presentation in GeekPwn, the people who are in FW 3.55 would want to update to 4.0.1, without having to update to 4.0.5 and lose to opportunity to jailbreak (ouch)
Lets put clear that this works for ALL the FW, not to the specific 4.0.1, but in this one we gonna update to 4.0.1
Requirements:
- A Flash USB of 1GB at least
- A PS4 on a FW lower than the one you want to update (Sorry, not downgrading on this one)
- The update file (Link in first step)
- A PC
0- If you installed a PS4 Update Blocker you'll need to Remove PS4 Update Blocker before you can update your PlayStation 4 Firmware version.
1- First of all, you gotta download the 4.0.1 FW in a PUP file, which you can get clicking this link (mirror here).
Note: if you want another PS4 FW update, check this page (mirror here).
2- Now, format your USB to FAT32 (This will wipe all your data, so make a backup!)
3- Now, make a folder in your flash drive called "PS4" (without the ") Remember it gotta be in UPPER CASE.
4- Inside the PS4 folder, make a folder called "UPDATE" (again without the ") IN UPPER CASE.
5- Copy the file you downloaded at the start of the tut to the UPDATE folder.
6- Rename the file to "PS4UPDATE.PUP"
We're ready in the PC, now lets go to the PS4.
7- First of all, shut down COMPLETELY your PS4.
8- Now, put your finger like if you were turning the console on, but release it when you heard the second beep. In other words: Press and hold the power switch. You will hear one beep, wait until you heard the second beep.
9- Connect the FLASH drive to the PS4, followed act connect via USB the DS4 (Dualshock 4 Controller) and press the PS Button.
10- Select the "Update FW" Option (I think is opt 3) and select via USB drive.
11- Follow the steps on screen, and select "Okay"/"Accept" in everything.
The PS4 Gonna reboot a couple of times, and guess what, you have successfully updated your PS4!
See you next time!
Thanks to @bodeg for letting us know about this tutorial in the PSXHAX Shoutbox!