Do not turn off your computer or disconnect from the power source while updating the BIOS as this could harm your computer. During the update, your computer will restart and you may briefly see a black screen.

Before updating, please read the installation instructions and important information noted below.

Dell OptiPlex System BIOS, A20

AUTO INSTALLED This file was automatically installed as part of a recent update. If you are experiencing any issues, you can manually download and reinstall.
The following problems in the A19 BIOS were corrected to generate the A20 BIOS:

1. Add support for autoshutdown call for win95 and NT.
2.Properly disable cache if no l2 installed.
3.Make beep code for no memory 1-3-2.
4.Remove 3f6/3f7 from floppy resources.
5.Fix incorrect BASE address stored in on-board S3 configuration space.
6.Assign IRQ's by slot, not function.
7.Support 16-bit IO arbitration, if no 10-bit IO present.
8.Deactivate iorangechk in PNPISA cards.
9.Allow port 102 to be used by PNPISA device.
10.Remove 3BF from the VGA resource table.
11.Use IRQ 15 last when searching for free IRQs for PCI.
12.Turn off S3 PCI disconnect.
13.Allow IRQ 12 use if mouse disabled.
14.Disable bus-master bit in IDE registers when onboard IDE disabled.
15.Fix possible bad year when auto-power-on is enabled.
16.Put 764/765 into bad_dac_snoop_table (force dac snoop off).
17.Allow dac snoop enable for onboard vga when feature connector on.
18.Allow use of 'non-2k multiple' ISA option roms (new ibm TR card).
19.Make copyright notice say 1997.
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Version

A20, A20

Release date

15 Aug 2000

Download Type

System BIOS

Category

BIOS

Importance

Optional
Dell Technologies recommends reviewing this update to determine if it applies to your system. The update contains changes that impact only certain configurations or provides new features that may or may not apply to your environment.
Available formats

File Format: ZipPack External
File Name: GX_A20.EXE
File Size: 124.02 KB
This is a large file. Depending on your connection speed, it may take some time to download.
Format Description:
This file contains a compressed (or zipped) set of files. Download the file to a folder on your hard drive, and then run (double-click) it to unzip the set of files. Follow the instructions to complete the installation.
To ensure the integrity of your download, please verify the checksum value.
MD5:
Not available
SHA1:
Not available
SHA-256:
Not available

By downloading, you accept the terms of the Dell Software License Agreement.

Additional details

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OPTIPLEX 330 SYSTEM BIOS
OptiPlex System BIOS

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