There is no such Model 970.

• OptiPlex 960
• OptiPlex 980
• OptiPlex 990

You will need a FREEDOS boot CD and a FAT32 USB 2.0 flash drive.

You F12 Boot the FREEDOS CD and then type C: to get to the FAT32 USB Drive to run the bios update File.  If you have a 990 this is NOT an option for A14 bios because its larger than 2 megs which is the max size freedos can use to install a Bios Update.

Larger than 32 gig and or USB3 flash drives won't work as they are EXFAT.  This CD should be burned onto a CD-R disk at 1X 2X or 4X speed max.

CDROM “legacy” installer

https://www.amazon.com/SanDisk-Cruzer-Blade-Flash-SDCZ50-032G/dp/B00IFU6DU8/

Hi @Akers303 ,

Wonder if you're talking about Optiplex 790 actually.

You may try to create a DOS bootable USB stick from another Windows PC by RUFUS, download the latest BIOS, say A21 for 790, and copy to the USB. Then you should be able to boot into DOS and do the BIOS update from command prompt.

Bios update files larger than 2 megs wont work via DOS

Hello @speedstep

 Bios update files larger than 2 megs wont work via DOS

****************************************************************

I know this is an old thread, but thought I would reply for your edification.

I just used DOS, booted from a usb flash stick. I flashed A22 bios on a dell 790 mt. This was about 30 minutes ago, and seems to have worked. I'm using the machine now, and it shows a22 bios (hwinfo, speccy, etc.)

The file used was O790-A22.exe, downloaded from Dell. Size was 5.58 MB (5,854,368 bytes), which is considerably more than "2 megs".

How did this miracle happen ???

Now, I'm a little bewildered. Maybe you can explain in more detail about the 2 meg dos limit.

Thanks.

Freedos is still available.

MSDOS 6.22 may work for some models.

A DOS WINDOW in any version of windows WILL not work.

Making an MSDOS boot floppy means your flash drive is 2 gigs FAT16.

FAT32 is not supported with actual MSDOS.

There are many posts where bios updates do not work or worse Brick the unit.

This is why I recommend getting a Dell XP disk and a small hard drive up to 80 gigs and installing XP then chipset then management engine driver

then running bios update from that drive.

Once done you don't need it anymore.

A22 for the 790 is 5.58 meg.

https://dl.dell.com/FOLDER05078555M/1/O790-A22.exe

Some OS will have issue with files this large due to the amount of memory available for dos.

Note 1: You must provide a bootable DOS USB drive. This executable file does not create the DOS system files.

Being larger than 1.4 megs means it will not fit onto a floppy.

There are other problems depending on what the bios is at the time of update.

If BIOS version A04 or earlier is currently installed on your system, you must first update to BIOS version A05 and then update to the latest BIOS. If BIOS version A05 or later and BIOS versions before A10 is currently installed on your system, you must first update to BIOS version A10 and then update to the latest BIOS.

Your miracle is in no way as easy as you describe.

The 2 meg limit has to do with the memory map for MSDOS.  Especially for systems with more than 2 gigs of system ram.

Freedos bootable flash drive

Flash drive FAT32 formatted capacity= 244 MB

Works fine with 5.58 MB flash file added.

No need for an XP installation on a hard drive.

244 meg would be FAT16

up to 2 gigs is FAT16 not FAT32.

244 GIG would be EXFAT which DOS does not support.

It's formatted

Fat 32

Windows gives a choice of NTFS, Fat, Fat32, exfat.

I chose fat 32. I just formated another identical flash drive.

Also

FAT 32

These drives are nothing special ... They are cheap freebies handed out at trade shows years ago.