EPROM BIOS flashing, the good , the bad and the ugly.   
HP.com Centric.
Or how to Brick a PC easy?

BIOS is ROM Machine code or Firmware or Software in Silicon as some say. I hacked Freedos here.
Most folks flashing their PC , brick it in 5 minutes flat. (LEAVE BIOS ALONE, do not flash it,  unless real HP technicians told you to)  Flashing any PC is loaded with RISK.
The newest BIOS has new UEFI rule , no regression allowed. (so if you flash it ,now, and it fails, how can you regress to the last version?)
BIOS Runs with no HDD in place,  (except HP magic F11 key, that needs the HP recover partition in place to function)
Most dead BIOS screens (all dead) are from bad power, or dead screens.

Flashing means to burn the EEPROM cells.  A.K.A. programming or in the very old days' fusing the PROM's)  EE = electrically erasable and alterable.
The term Flash was used when EEPROM started burn way faster than the first ones made from Intel or SEEQ.
The FLASH simply charges up the MOS floating gates. (after erasure)  this is just ONE BIT CELL. (1 of 8 million on mine)
This charge can rest there for 100 years. (from top makers like Microchip(tm) "data retention spec." End CMOS101.

The trick is to burn the BIOS ROM and not brick it.  (  it just like owning a brick, forever. (usesless as a brick)  (burn = flash= programming it)
The best way to burn in my opinion is to burn with REAL DOS (Freedos) is best. Due to its non-multitasking OS features. (a blessing for sure) {a generized statement}
The other way is to have  smart boot block section in the BIOS ROM that (is frozen there) That has a BIOS load feature (HP uses "power-on + winkey+B)but is dumb, the HP code is no good for letting you find a file say on a USB STICK.
The BIOS boot block excels in the regard , my ASUS M5A99x mobo has in its BOOT-blocks, as EZ_FALSE_2, (in the BIOS advanced menus, that lets you up load  USB stick binary and burn it safe and sure)  HP is weaker in this regard.
This is in ASUS manual on page 3-32... btw.
Never flash burn in Windows ever, it will BRICK your  BIOS so easy.
Now all ways  from SUNDAY,. both good and bad and hacks. My 2009  LT does not support W10, and for sure, the only BIOS making file fails. SP73931.exe    so I hacked it.

BIOS FLASHINGwhy it is best done by a PRO TECH and the pitfalls .  (Flashing means burning new machine code into BIOS EEPROM CHIP) It is for sure non trivial.

Flashing can be easy sure!, but is loaded with RISK: ( the older the PC; the more risk)
If you play with BIOS flashing it, then kill it dead,  what is your PLAN B? Oops a Daisy , I killed it dead., now what?
RULES: (how lucky do you  feel today?)
The Computer must compute, that means with no errors.!   (many things can fail here with 3billion transistors or more...)
To do that takes what, GOOD POWER,  that means all DC power buses in the PC must be at spec. and no shorted modules inside wrecking POWER. ( power is every thing, so is regulation of same)
Do not flash if your CPU processor is overheating, or with bad RAM or any other major hardware failure on the motherboard or you risk causing the second hard failure a bricked PC with dead BIOS.
Do not flash if the PC looks like this inside.
Do not flash BIOS if the main A.C power pack is weak or the Main Battery (huge) is bad  (or weak and worse SHORTED)!
Do not flash if the BIOS says the HDD(SSD) is bad (remove it), or if Crystaldiskinfo says  it is bad, the HDD can short and overload power supplies, 5v or 12vdc.  The BIOS CHIP needs good power bus voltages to run right.
Do not flash the BIOS if the CMOS NVRAM COIN CELL IS DEAD or weak over 2.9v is good, below is NOT OK. (or is this the real cause of problems? and  $3 cure... !)
Do not flash until a HP real technician agrees or gives you the correct version and perfectly matching BINARY files.  (or you will brick the PC) matching all lines seen here!
Do not flash for fun, or if your BIOS screens all work,  and the F9 key will   boot to all things in its list , if only the HDD will not boot, then BIOS is ok,  the HDD is bad or the OS on it is DEAD. fix  that only.
My F9 key can boot to CD/DVD and to SD/cards, if all this works , then the HDD has problems NOT THE BIOS, forget BIOS now. (next would be HDD testing extensive, I use Knoppix v7, live boot DVD )
I can also boot my 2nd SSD drive , that replaces my DVD drive bay. (my F9 key boots to 7 things, if you do those tests, you learn (maybe) omg ,it's just the HDD messing up. oh my gosh, Knoppix runs great above? BIOS IS OK.
Do not attempt to use a USB HUB's of any kind , only use the direct USB jacks on the PC when flashing. (and be aware some can be dead at boot up, try them all? or turn on USB legacy mode in BIOS)
Last, never flash under WINDOWS directly ! EVER.
I can insert a known good empty hdd into the drive bay 0,  and then install any OS to it (hark even LINUX), and it works ok. why are you flashing the BIOS?
If you pick the wrong  bios.BIN file and it bricks your PC, what then? It can be super hard to fix that. (HP has  binary reset that only works with you UUID code, as covered below)
Or if your PC was made in say the year 2008 , the bad solderballs are real.(keep in mind other chips can fail for this same reasons,  due to RoHS, compliance.
There are many ways to do the FLASH (burn), not just one. (each has its own set of risks,  FREEDOS is best in my opinion.
I think all HP PCs new, now have FREEDOS to burn the BIOS,  using the downloaded, stick burning program SP12345.exe. (matched to your exact PC,  most noob persons seem to get this WRONG)

ALL WAYS To FLASH: (from poor to best) to burn... (DOS Is best)
  1. Winkey+B wayBIOS Flashes BIOS 1/2 the time fails , due to It not finding this file )   ( I do not trust this way at all)
  2. Flashing under windows (never do that ) HP don't offer it or online flashing (other PC makers tried this and wished they never did !)
  3. Flashing with the HP  3-in-1 key way , HP extends BIOS this way.... (or using the HP 3in1 extender boot stick to make it SMARTER ) (I would use  this before the above.)
  4. Last and not least (best) is the FREEDOS way, that HP uses.... seen here, this mode uses REAL mode of the processor, max safe. 
  5. HP USED REAL DOS to make the burn stick for up to W7 and then changed to FREEDOS at W8/10.  This is because MS dropped the DOS DLL files to DO real DOS.
  6. BCU way, I will never try this ever.( put here to have full coverage, only)
 These files are on all HP PCs made (at least 1 file) in the HP-tools partition. This is a fall back file seen in Previous.  (regression binary, but now is defeated by UEFI rules ) sadly.
My HP8540w  , if the HDD is new or upgraded to SSD they will be missing.
The HP doc's alludes to a way to get Winkey+B to work off a USB stick  , I FAILED to get that to work ever. (my guess is, if above is missing It may look on some or all USB sticks, but mine fails to find it)
I loath Winkey+B way,  and its lack of a simple bios file brower ( even just allowing you to change to disk 2 a USB stick is needed here and is not there)
The other factor here is the new BIOS for UEFI , rule one, is no regressions allowed, so tell me how does Previous  work,  answer; IT CAN'T can it.

If you read your PROBOOK BIOS rules, it says no REGRESSION path after flashing UEFI; this newest update.  ( some PC have 8 UEFI updates,  and going backwards is NOT ALLOWED, today)
I will avoid UEFI , until say year 2025, until the bugs are gone,,, (I just never want to land in UEFI H3LL ever, life is too short for that at my age)
First read this, HP document and try not to get confused .

Let me review the above page. link. (it keeps saying DOS over and over )  The word DOS means nothing lacking a makers name and version !

The doc above is dated, 2005... ( more digression but useful for any one  doing a W10 upgrade this is a PITFALL) {but not on a new W10 PC}
It's not MS DOS 1 to 6.2 nor is it Digital Research DOS7 (aka. DR-DOS, or Novell DOS) (none of these run on modern systems, usually for lack of video chip support)
Nor is it the famous "command prompt" or CMD.exe (aka brain dead DOS) not even command prompt run from say a MS or HP install CDs !
I now learned what you get, real MS DOS (Diskcopy.dll ) say in W7, but at W10 you get  FREEDOS. (secret solved)
But on my PC, the max OS is W7 for HP Support , after the free update to W10 , this SP12345.exe program builds a dead USB FLASHING stick. (now I know why and the cure ,below)

The fact is the HP flash stick flat will not run on any W10 OS installed computer.
The cure is FREEDOS:
The program  Flashbin.exe?(runs in REAL MODE !) This is a blessing, it can't fail you,  unlike nasty  preemptive multitasking as WINDOWS LOVES to do.
Always burn in X86/x386 Real mode.  (it is the most safe of all) 
But reading every word,  the above HP burn DOC1,   it does state FREEDOS. clear as day. (page 25) see 2017 report on FREEDOS and FLASHING !
Some Freedos versions might fail. (use the newest one, always so all video GPU chips can work is very important)

How to flash safely. (risk wise)?   My PC boots to over 7 devices, if all these work ok, but the HDD do not FLASH it. (fix the HDD)  (never flash if only the HDD does not boot)
  • If a Desktop?, consider using a UPS power pack device.
  • On laptop same and not use the Battery if you suspect it is bad, many are , if the charge lamp stays out , you may be ok here.  Best is  new freshly charged battery or none. 
  • Use only Freedos boot stick from HP. (the correct one can be hard to get,  not matched to your EXACT PC) by full model, P/N product number and even serial numbers can ID unique MOBO's..!!!

Example of flashing a modern HP laptop is next: HP8540w.  (I flashed 5 now) I buy used LT's and give them to many in our  family.

SP12345.exe way! ( ask HP for this correct file)
(this is the BEST WAY) It flashes using CPU real mode and not Windows nasty preemptive multitasking OS.  (burning and doing 2 things at once is SO WRONG)

HP uses FREEDOS: (go to your service page at HP.com then click Software and DRIVERS  and OS and list click BIOS,  if missing see all OS for the newest BIOS .
The HP page search is poor, it has poor or weak fuzzy logic,  (8540 finds nothing, but 8540w  finds my PC as does 8540p)

Details:The HP and RUFUS programs use a different DOS, starting with Windows 10.  (before that it uses cloned (legal) Diskcopy.dll and at W10 it uses FREEDOS.)
One cute fact on what I call hidden DOS. (inside windows the old DOS hides in diskcopy.dll,  Microsoft deleted this file in Windows 10 this fact causes FREEDOS to load.
My HP Stick maker uses the wrong FreeDOS under W10. (my guess is diskcopy is missing (it is) so the HP code loads null files. and fails to boot. The cure is below.
 (in FreeDos live ,  I type, "VER" and get " kernel 2041 build, Feb.7-2012 frecom v:0.84-pre2")
The HP stick maker, program uses Build 2036.  (and has issues)
  The HP USB flash stick program for my HP fails.  (for both freedos or diskcopy.dll reasons, I'm not sure but files are for sure missing)
The proof is here,  I patched in a good FREEDOS to work. (I have scrap box full of bad MOBO's  this one has a broken KEYboard connector, so I am free to wreck it more testing, here, no risk by me)
This seems difficult but is not , I only copied some files. over.
I will now use my , 2010 laptop Elitebook 8540p , to demonstrate how FREEDOS runs perfectly   and flashes,  using HP Flashbin.exe (to start)
2 ways exist, CD boot or USB stick , floppy drives do not exist now.
I get and build a  Freedos new from the real makers,  on my hp8540w , it runs perfectly off this new stick, that I made,..  type VER enter-key , running, to see what you got. ?

The first Step is HP documented method (but works only on W7) (my filenames below only work on my 8540w Laptop)
FYI:  facts, for the curious:
I downloaded my HP , SP73931.exe file from HP and used 7zip prog to open this archive to see what I got,  there is RTF file there inside to read, and we see it also has Freedos kernel there.  (nice but is dead on my w10.)
This EXE is the HP official USB stick burner (pendrive/usb flash stick/ USB keydrive) I call them USB sticks.It burns a stick for you..
Here we go... we launch this EXE  program this PC or  and extra PC !
Run HPQFlash under windows OS,  Best is known clean non infected PC.

The first bullet below "Initite", don't use this, IMO.  (after all windows is running now, and windows is a dangerous multitasking OS)
I'd never pick the first bullet choice ever,  this OS W10 is a preemptive multitasking system and using this mode is HIGH RISK, (Google the million failures online, sad to watch this)
Pick Create a bootable....USB stick.  (this will FREEDOS, on all new PC's)
Pick USB disk on KEY (HP KEY = USB memory stick) they call it a KEY =stick = thumbdrive,= usb dongle = USB-mem or UDISK.
 This step simply burns the stick with Freedos and the BIOS files, and REAL mode BURNER app.

After this BIOS update has been installed, you see "previous BIOS versions cannot be reinstalled". (oops no  plan B !)UEFI BIOS rules, now..

The program  runs under windows and was downloaded from HP , driver page under BIOS matching your exact system , perfectly! (ask HP first, they may need your system serial number (a FACT)

sp73931.exe (8540w only) runs and shows this window. I click USB Disk (they meant KEY) then OK.
BTW way any sizes USB memory stick works here, the files are tiny .
Next we see this and I push START.
This creates a bootable USB STICK with FREEDOS and 3 key files.  In my opinion this is the only safe way to burn flash the BIOS update. 
The start button goes ungrayed to tell you its done.

This next photo below is the total contents of the SP73931.exe file from HP.  
My stick is DOA, due to wrong DOS used, by HP.  HP in this program does not support W10 only W7/8   ( this is not HP fault, they do not support W10 at all in this PC but mine runs mostly ok, but not this...)
7zip view of SP12345.exe (any one, mine is below) clearly you see it might use FREEDOS. (or might use MS diskcopy.dll internal code, for sure RUFUS does that... )

this is my 7zip View if the SP73931.exe file.   (HP warned me it's not for W10)
This is a one way trip, but if you beg at HP.com direct, they can give you a zero'ing out program that clear the BIOS ROM  and then you can repeat the step above using the correct and proper matching files. (and HP secret)
UUID means universally unique identifier
The zeroing.BIN must match your system UUID key, 128 bit key. or is  the file found my be USELESS.
if the PC boots  the command prompt for getting your UUID is  to type. (pasting the below works)
wmic PATH Win32_ComputerSystemProduct get uuid

Lacking  a UUID code, you must call HP and  they use your PC bottom service tag serial number to match you up with all BIOS flash files.

MY W7 to W10 Hack is here:

CURED: (solved DOS/Freedos errors) (I have now 2 FreeDos sticks one good from FREEDOS ACTUAL,  and one  HP bad, the cure is simple)
I copied the 2 files(HP only, one BIN, one EXE) off my bad stick and copied them to any /temp/ folder on my HDD.  (copy stick to stick works too sure)
Then I  copied these temp fails to my good bootable stick (FreeDOS 1041 build , running ok stick)
Next I  boot and behold FREEDOS RUNS now, the HP app runs now, automatically (eRompaq.exe) config.sys does the Erompaq.exe launch.  

I then burned BIOS F60 ok. (it warns me, no regressions allowed)
The below is a working (CP + no hidden files , turned off in explorer, view file no hides, and all shows on) (CP = control panel)

  The HP stick maker program failed to put on the stick Command.com and uses 2009 very old kernel.sys, or older.. (using VIEW = no hidden files) keep in mind config.sys in the DOS days is  simple text file you can read.

Created by Rufus 2.3.709 + , my added, HP files 
The key files to  move are config.sys, xxxxx.BIN, and eRompaq.exe. (form the HP dead stick to the good stick that Rufus made)

This is running under FreeDos new build 2041.. after I rebuilt the freedos stick from scratch. (IMO always use the most current FreeDos!) 
One thing I do not like here, is the lack of the BACKUP button below App.. (we've had this since  the first EEPROM flash ROMs were used)

I get only one choice, to burn.  (in the olden golden days, we DID  backup first!  and was are PLAN B  recovery... dig?)

This point is now moot, sadly due to the UEFI rules,  no regression allowed...(wow)!!! Not only that but this rule kills dead the (power on +winkey+B ) reload method ( this was the failsafe method back to day1 )
I have no love for UEFI at all,  it can be a big pain to use,  for sure trusting MS, GPT2EPT.EXE , program ,  to convert any HDD. wow that be risky. (but I digress)
Warning HP on some PCs had up to 8 UEFI patches,  ouch.  How to deal with that, I don't know, but I do avoid UEFI.  (say until, year 2025 when patch 100 comes out. LOL)
Never buy the first year car, never buy PC with first year, UEFI..... yah?

This is the best way. Bar NONE. seem me do F50 to 60 and is a one way trip.. (on my bad MOBO as  test)
This is by far the best way to FLASH! (under DOS)
Now we can see why FLASHING is so RISKY.
The above method (program app) is the best way.... USING FREEDOS build #2041 up.
If this fails, after hitting Update, try one more time, luck happens.  (for sure never do this if the PCs power supplies are IFFY (weak or odd in any way)
Try all USB ports. 1 by 1.
Even remove the HDD and DVD drive, can make the power buses, more robust. (and quiet)
Unplug as many things as you can while Flashing any BIOS.  ( that includes leaving that old crappy LT battery out  of PC and  fresh new COIN CELL added)
Are you still failing the flash?, then call HP direct ! , only they have a solution!
More examples , I love photos they speak deeply....
The boot screen looks like this (mine)  ,InTel   i7, HP laptop, 8540w. ( see long file names are truncated in DOS) I'm issuing DIR /A here,  other commands can  be seen here.
The bin file is the , BIOS binary burn file.  Typing Erompaq,  below will run the above program. (your BIN is not MY BIN, dig?)
8540w actual.

HP PC 2009 up have a BIOS page called System diagnostics, and in the list there is.  BIOS MANAGEMENT.  (OLDER PC'S you many need to do all this)

On that page is a selection, to "UPGRADE BIOS" or roll back (if the HP-TOOLS folder are missing on Drive C: this fails, to roll back to DAY1)
In my case, F60 version BIOS states, can not be rolled back ever.  (in the details files with the update and just before the burn it warns you a 2nd time, about this new UEFI fact.)

I have just learned there is HP diagnostic boot stick now as seen below..., (this is far far better than the BIOS code burn)

The below acts like and extension to F2 Diagnostic BIOS menu's.

HP PC Hardware Diagnostics 3-in-1 USB Key V3.8  (1.9GByte size)!  Be patient it takes a long to time to burn the stick! ;Then Boot it.

It states it  can correct corrupted BIOS. The above has over 600 BIOS file there...(but no clue about what  fits what....)
The Above stick once made, on to the USB stick, you boot the PC then press F2,  this stick acts like and extension to the BIOS F2 menu.  (amazing ways this...)
The new menu below has many new tests + a new BIOS update .
 This new update allows me to Browse (as seen below) for any files now, even adding 2nd USB stick with my F60.BIN file works now.
Note how HP added the browse (please select....files system) and also shows DRIVE LABELS< now.  hark what gift to man kind.  It even sees my Day1 backup in Hp_tools ....
My   Freedos stick below  has my 68CVD.bin file.(mine only not YOURS) (this is the new  browse feature... nice)  I may only run on newer PC, not sure. 10 years or newer.

end 3-in -1 key: (above) this only runs on newer PCs. HP web site shows older version running on XP for example. (I'll never go there again, XP is dead)
The only backup BIOS mode (feature) I could find is seen here, in figure 5.

BIOS updates BIOS: ouch ! WINkey +B (H3LL?)  
I don't like that way due to its being so blasted DUMB. (lacks a browse to file feature, nor it's rules on file names, my wild guess *.BIN)
The HP (magic) power on while holding WINkey +B (or V)
(btw some HP blink the caps lock key 6 times to tell you the BIOS is corrupted and some 8 flashes) (pre 2015) 6= BIOS authentication failure !   (2015+ is 2.2 blinks 2 slow , 2 fast, repeat,)
Blink codes changed in time like the Weather. BLink(beep) codes are a PAIN for everyone.

My PC is F60 BIOS so the older F50 HPTOOL BINARY is now USELESS, (no roll backs allowed now)
This magic and blind and dumb code and  runs and finds this file. (if not found , it provides no browse to force it to a BIN FILE) MAX PAIN here.  It can however, take you to DAY1, BIOS , as shipped new.

BIOS FLASHing (burning) 

Next BCU methods. (Avoid IMO)
 This only works with WMI-compliant PCs and BIOS.
This utility is for deploying 1 BIN file burn to many other same type PCs.
 Read about what it can do here. (I thi nk it's High risk!)
I see that there is an autoback up, done by some HP processes, seen here.

HP has this BCU Page , BIOS Configuration Utilities, the newest one supports all W7 and newer PC's by HP

Things that make your BIOS binary files different.   (when selecting the correct flash binary files, at HP  SP12345.exe)
  1. What motherboard is there. (MOBO)
  2. What BIOS chip is there. (programming rules matter (flash chips)
  3. What Video GPU chip is there,  some same model PC had 3 types used in  the model run years. (getting this wrong , you get black screens super easy)
  4. What processors it can use, some BIOS updates add newer processors. Some MOBO are intel, and some are AMD,  getting this wrong is  hard FAIL.
  5. What ram sticks can be used,  based on PnP scans of your sticks.  The newer BIOS may add newer DDR ram  chips allowed here (chips on sticks)
  6. Sound chips (some mobo have 2 or 3 used in a production run.)
  7. WIFI modules used. (and chip)
  8. Ethernet chips used.
  9. What USB chips used,
  10. and more lots more....  matching the BIOS files up correctly works best, guessing not.  Ask HP for the correct BIOS flash files with due care.

If not sure?, avoid flashing like the plague.

version 1.  5-9-2017