Updating Z400 BIOS

[DGroves]

please use this sites "SEARCH" function your question has been asked/answered numerous times 

the 400/600/800/420/620/820 workstation models all use the same update procedure

we recomend updating from the Bios or from DOS and not to use the windows update method

the latest bios can be found on the HP site ( for your model computer) and the bios file also includes directions on how to update

https://support.hp.com/us-en/drivers/selfservice/hp-z400-workstation/3718668

[naxbc]

I did! Procedure described doesn't work. And I'm not trying to update BIOS, I'm trying to recover it. Tried BIOS image CD and failsafe boot. Nothing!

[Ro808]

Recover from what?

Did you accidentally chose the "compute" option for your graphics card in the bios settings?

[DGroves]

also, if trying to recover a z400 bios why did you list "updating z400 bios" as the main descriptor?

and just why do you think you need to recover the bios?

[naxbc]

No. Did you read the previous posts? I was updating within Windows GUI and it BSOD'd while it was writing on BIOS. Trying to recover ever since.

[naxbc]

Because I was trying to update BIOS!!!

And because it BSOD'd while it was updating!!!!

[DGroves]

i don't read each post in a multi page thread, and it's considered bad form to hijack a existing thread by posting a compleatly diffrent request you should have started a new post (if nessary)

however again my first post holds true, if you use the search function you will locate several posts by "SDH" who has detailed how to perform a bios recovery

[Ro808]

Iam sorry, I must have overlooked your description of the issue at hand
Bios is probably in an "in between state".
I suppose you've tried all recovery options pointed out by SDH, including c-mos reset and the jumper option?

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[naxbc]

No worries. Believe me when I tell I tried all approachs. Nothing worked 😞

[Ro808]

Took this comment by DAN_WGBU from an archived thread.
You've probably followed the proper procedure, but anyway:

Here is how the CMOS reset works:

- The AC power cord must be removed, and all power drained from the system, before the CMOS reset button works. This is a design feature, to prevent the CMOS from being cleared if someone accidently pushes the CMOS reset button while working inside the chassis.

- All power must be drained from the system before the CMOS reset works. Newer systems can take up to 2 minutes to lose the on-board standby power after AC power cord is removed, which is much longer than previous generations. One way to speed up the process is to press the power button several times with the AC power cord removed. The system will try to power up, then shut down quickly, but this helps to drain the system quicker.

- After the AC cord is pulled, it is hard to estimate when all power is drained. Waiting 2 or more minutes seems like an eternity when one is watching the system. 😉

- It is only necessary to push the CMOS clear button once, for a short time. Holding it down longer does not make a difference (as long as power is drained first).

Which beep sequence do you hear, if you try to power-on without any RAM modules installed?

After the C-mos reset it's good to first remove all RAM modules and try to boot with one randomly chosen module in slot 1.
If it fails, try another module in the same slot (slot 1).