Beep code at start of boot sequence

[Ron333]

Upon pressing the power button this machine starts beeping.  It is a sequence of 6 long beeps (approximately 1 second each with about .5 second between them.  The sequence then repeats a second time and the computer finishes booting and then Windows 10 lock screen comes up as it normally does.  The problem is that I cannot access the BIOS at all.  None of the keys work that normally would (Esc, F2, F9, F10, F11).  The screen remains blank until the Windows 10 lock screen appears.  I think I might have changed something in the BIOS that had to do with legacy support and that is when this problem appeared.  But now I can't get back into it to try to correct the problem.  Also I cannot get to the boot menu in case I would need to boot from a CD, DVD, or USB device.  And I cannot access any recovery options in case they would be needed.  Can anyone tell me what these beeps mean and what can be done to correct the problem?   I tried all of the suggestions I could find in these forums including removing the CMOS battery to reset it, reseating graphics card, reseating hard drive connectors, etc.  Even tried to do a BIOS recovery which woud not work as described.

[TheOldMan]

Sometimes getting into the BIOS is a chore.  What I tell users to do is, from a complete power off situation-

Start tapping the Esc key.  Keep tapping the Esc key about every half second, then press the start button.  That should cause a pop-up menu to eventually appear.  Then pick BIOS setup.  You might have to try numerous times as it sometimes is a pain. Sometimes when using a USB keyboard, especially if it is not the keyboard that came with the PC, it will not acknowledge the keyboard until Windows loads the USB drivers.  If that is the case, use the original keyboard.  Also, since that PC has both USB 2.0 and USB 3.0 ports, use the USB 2.0 ports for the keyboard.

BTW: disconnect every thing except the monitor and keyboard when trying this.

[Ron333]

Thank you for your reply.  I tried your suggestion exactly as you described but it did not work.  I had tried that before but tried it again just to be sure.  I have no video signal at all during bootup until the Windows lock screen appears.  And everything after that is normal except that the power button led is not on as it normally would be along with another exterior red light.  As I said in my post, I believe it has something to do with a setting that I changed in the BIOS.  I believe I disabled legacy support which I had enabled some time ago.  Don't know why this would have caused this issue but I am  interested in the beep code sequence.  I believe it might give a clue as to what is going on.  I have also discovered 3 jumpers on the motherboard.  One is labeled "CMOS PW" and another "ROM RECOVERY" and the third is "FLASH OVERRIDE".  I recall having a similar problem with a computer several years ago that was solved by changing a jumper on the motherboard but I don't like tinkering with something without knowing what it might do.  Anyone know what these jumpers are for?

[TheOldMan]

I agree that changing the BIOS setting to disable legacy support should not cause the stated symptoms.  Also agree on not changing the jumpers.  Beeps codes usually are for reporting a hardware problem.  Most typical hardware problem being a memory error.  What is even more weird is the computer then boots and runs OK. 

The 6 long beeps, depending on the BIOS manufacturer could be either video card failure or Keyboard controller Gate A20 error.

[Ron333 · Accepted solution]

Well, it appears that I solved my problem.  I was trying to remember why I had changed the legacy setting and it came to mind that it had something to do with installing an upgraded graphics card.  So I removed the newer graphics card and reinstalled the old original one that came with the machine.  It worked.  I now can access the BIOS just as I could before and everything is back to normal.  Thanks to TheOldMan and anyone else who may have read my post and gave the issue some thought. 

[TheOldMan]

Thanks for reporting back.  It is those little details that are left out that turn out to be the reason, many times.  Such as a graphics card that was added, but left out of the things that are reported.

Thanks for clearing that up.