• ×
    Need Windows 11 help?
    Check documents on compatibility, FAQs, upgrade information and available fixes.Windows 11 Support Center.
  • post a message
  • ×
    Need Windows 11 help?
    Check documents on compatibility, FAQs, upgrade information and available fixes.Windows 11 Support Center.
  • post a message
HP Recommended
Microsoft Windows 7 (64-bit)



Purchased a HP Z800 tower yesterday. Installed W10 and flashed the newest BIOS on it. Everything worked flawlessly until I noticed hyper threading was off. This is when I tried to access BIOS on boot but noticed none of my keyboards were usable. I tried to reset the BIOS with the on-board physical button, which worked, but the system prompted a series of error messages such as time, asking to confirm with "F1". 


I had to drive over to a friend to use his PS/2 keyboard to have control of the BIOS. Now I can control the BIOS, but all my boot drives are gone ("no bootable disk found"). I tried to reset default settings via BIOS, which is when I started having loss of signal issues. Now I need to remove AC to get the PC to display signal after boot.


When I get a signal, the following occurs:


POST -> RAID window -> LSI MegaCorp -> no boot disk, press a key


I tried to use another BIOS, but I'm unable to downgrade. Everytime I use DOS-Flash USB via BIOS I get "error flashing system rom". Only re-flashing the current 3.61 works without an issue.


What am I supposed to do? I'm very limited configuration-wise because I don't have a PS/2 keyboard, so every time I want to try something I have to do it elsewhere. Boot options are IDE / RAID+AHCI, tried both without success. I've tried to run with a single RAM stick but the lack of signal is still present. My GPU is GTX970, could that somehow be an issue?


Boot block date is of the newer one, running dual E5620.



HP Recommended

first of all i would spend the  $12.00 on ebay for a ps2 keyboard, or buy a usb keyboard such as a logitech which will work


second i would download and read the z800 user and service manuals so i would have a basic understanding of what came with the z800 and how it's configured


third,  why do people think trying to flash a bios when they have absolutly no idea what's going on is a way to resolve it

when it actually will/does cause even more problems,.....stop doing things blindly it will only cause you more problems


fourth, the z800 has multiple onboard controllers SATA and SAS


both controllers require the correct  drivers , and knowing which controler is set as the main/boot drive along with the CD/DVD drive (if installed)


the most common setup is CD/DVD on SATA controller port 0 and boot drive on SATA port 1


however the drives can also be on the LSI SAS/SATA contoller ports 0 through 6 (see why reading the manual helps)


but the windows setup may not see the LSI controller, which is why the intel controller ports are recomended during setup. after win 10 is running you can move it over to the LSI ports








windows 10 came out after the z800 chipset was released by intel, as such it will have all nessary drivers

the only driver that you might want to update/install is the Intel Rapid Storage Technology Utility and Driver for Microsoft Windows HP sp60733


if you get a no drives found on win 10 setup and it,s not on the LSI ports  follow the directions below to load the nessary driver during the windows setup:


extract the files from the SP using winZip/WinRAR/7-Zip


locate the DOS folder, place it on your usb key, install the key on a usb 2.0 port and reboot/restart the windows 10 setup  at the search for driver prompt, direct it  into the usb key\dos folder, and it should now find the drive


while hp lists it as a win 7 driver, this is due to hp not testing the win 10 os on a Z800


intel who makes the RSTe drivers has tested it on XP-win-10


last, the Z820 uses the Intel® C602 chipset,  ( similar to the x79 chipset)

and the  z800 uses the Intel® 5520 chipset  (similar to the x58 chipset)

HP Recommended

Thanks for being straightforward!


I actually had a Z400 I played with for years before this,  I was never anywhere near bricking it so assumed I'd be safe on Z800 also.


Going through the manual everything makes more and more sense but why did you mention the C602 for Z820? How is that relevant here? Am I still missing something?


I'll start fixing the beast soon, still got to find that working keyboard. I did try two "old" USB KBs, one IBM and one Logitech. Also went on and bought a USB > PS/2 adapter without results. Ebay's delivery time up here north EU is 2 weeks and nobody sells true PS/2 KBs other than freaking expensive "gaming" equipment.

HP Recommended

Got the system fixed and upgraded to 2* E5645 successfully.


One last question: under full load the cores are running at 2530 MHz instead of the listed 2670 MHz. I've tried playing around with both Turbo Boost and Enhanced Turbo Boost in BIOS. Why is it being downclocked? Temps are fine.

HP Recommended

this is normal, intel does not say that every cpu will run at it's top  boost speed intel only states that under optimal conditions that the listed turbo speed is the max speed you can expect leave the bios settings at default


you need to read up on a bios setting BRFORE CHANGING IT, as blindly changing a setting is not the way to reliably increase system performance/stability

† The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the <a href="https://www8.hp.com/us/en/terms-of-use.html" class="udrlinesmall">Terms of Use</a> and <a href="/t5/custom/page/page-id/hp.rulespage" class="udrlinesmall"> Rules of Participation</a>.