You can change BIOS password using iDRAC. This depends on "Password Status" BIOS setting and whether iDRAC have all details on BIOS to change settings. Some times iDRAC will not allow to make BIOS settings if the server is not completely booted.  Can you login to iDRAC and traverse to "System Security" section of "Configuration -> BIOS Settings" page to check current setting for Password Status?

• If this attribute set to Unlocked state then you can change BIOS system and setup password from same page using iDRAC. You no need to enter old password for this option
• If it is set to Locked state then you can change only setup password using iDRAC. In this case you can change "Password Status" attribute first then later once applied use iDRAC only to change both system and setup password

You can use PWD_EN jumper setting to disable the password. You can refer below link to identify jumper location and details on resetting password using jumper. If you use NVRAM_CLR option it will reset all BIOS setting to default including passwords. This should not impact your setting on Power Edge RAID controller like H730, H740, H330, HBA330 etc.

https://www.dell.com/support/manuals/en-in/poweredge-r740/per740_ism_pub/system-board-jumpers-and-connectors?guid=guid-7233c18e-b255-4620-be3d-c1a348083558&lang=en-us 

https://www.dell.com/support/manuals/en-in/poweredge-r740/per740_ism_pub/disabling-a-forgotten-password?guid=guid-0cb73b4f-8b9d-4c1c-a251-9e693591bbe0&lang=en-us 

DELL-Shine K,

I want make things clear, If I use PWD_EN jumper settings (from 2 and 4 - Default) to (4 and 6) to reset, then boot, after boot, return the pin to 2 and 4 , then boot again.

This will not affect the RAID configuration? Only the BIOS will load to defaults and erase the BIOS password configured?

thank you

PWD_EN jumper is only to clear BIOS password and it should not clear any BIOS or PERC controller setting. Which storage controller you have on the server? Did you got a chance to try resetting the password using iDRAC?

Hi, Dell-Shine K,

Sir I forgot to mention that we cannot log-in on the windows admin user, maybe it is not possible to reset via idrac?

thank you.

You can launch iDRAC remotely if you know the iDRAC IP address. If iDRAC network is not configured then you can launch iDRAC using a USB cable and directly connecting to the iDRAC Direct USB port on the front of the server. You can get more details on this from below link

https://www.dell.com/support/manuals/en-us/idrac9-lifecycle-controller-v4.x-series/idrac9_4.00.00.00_ug_new/accessing-idrac-interface-over-direct-usb-connection?guid=guid-2c43a175-3dd3-4a12-b747-d17c08e5bef6&lang=en-us 

You can find location of iDRAC Direct port from below link

https://www.dell.com/support/manuals/en-us/poweredge-r740/per740_ism_pub/right-control-panel-view?guid=guid-e4659218-c3db-4037-a9bd-3c5d00092b72&lang=en-us