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Summary of changes for BIOS update - ThinkCentre A50 (type 8320, 8419) / A50p / M50 / S50 (type 8092, 8183, 8184, 8416, 8417, 8418, 8429)

version 2AKT51A

  • Fixes the MAC address displayed in Setup. This problem was introduced in BIOS 2AKT50A.

version 2AKT50A

  • Adds code to issue hard drive "freeze lock" command to all drives on return from S3 power state
  • Updates copyright message to include Lenovo
  • Adds new microcode for 0F29. Patch ID was 0021h, now 002Eh.

version 2AKT49A

  • Fixes a problem where the Colorgraphics Xentera GT 4 video adapter card fails in Windows. This adapter has two devices (0 and 1); we need to add _PRT entries for device 1
  • Fixes a problem where the 3COM Fibre Channel card causes BIOS setup to freeze. Don't get MAC address for any device but the onboard LAN.

version 2AKT48A

  • Fixes a problem where the asset tag is corrupted when the asset tag in EEPROM (POV-3) is longer than the one in flash. Limits the copy to the length of the flash string.
  • Fixes a problem in the Spanish language version of the Setup utility where the UUID is truncated
  • Fixes a problem where the BIOS flash diskette crashes if a wrong key is pressed. This was not a BIOS change, this is fixed by a new phlash16.exe, version

version 2AKT47A

  • Updates the fan control in an attempt to balance both thermal and acoustics. (Increases fan speed gradually by small steps instead of a big jump. Disables fan speed hysteresis when temperature gets above the voltage regulator overheat threshold, to cool it quickly.)

version 2AKT46A

  • Adds new microcode for 0F34 (patch ID was 0Eh, now 13h) and 0F41 (patch ID was 05h, now 09h)
  • Adds a fan control update that will skip the voltage regulator temperature test on the small-form-factor chassis

version 2AKT45A

  • Rerelease of BIOS 44A

version 2AKT44A

  • Fixes a problem where the system will hang at boot when TCPA is enabled and a long bad password is entered
  • Fixes a problem where the system cannot extend PCRs 8-15 using INT 1A (TCPA)
  • Corrects the IOAPIC pin assignment for IRQ0/pin 2
  • Fixes the support for the 0F41 (Prescott E0-step) processor

version 2AKT43A

  • Fixes a problem where winphlash reboots the system unexpectedly
  • Fixes a problem where the LAN fails intermittently

version 2AKT42A

  • Fixes a problem where the Pentium 4 logo is displayed when the system is using a 0F34 Prescott Celeron processor
  • Fixes a problem where the system hangs while booting Windows XP if the USB optical mouse is moved during the transition
  • Fixes a problem where the system hangs with 0F41 (Prescott E0-step) processor
  • Increases SMBIOS Type 4 structure maximum CPU speed entry from 3200MHz to 3400MHz
  • Fixes a problem where the system hangs if AC power is lost during S3 standby

version 2AKT41A

  • Fixes a problem where the floppy diskette drive settings are lost when Setup is initiated from the IBM Predesktop Area
  • Fixes a problem where the system may hang during power on with a Token Ring adapter when the onboard Ethernet is enabled but the PXE Boot Agent is disabled
  • Fixes a problem on TCPA systems where the last five characters of the default asset tag string are not cleared

version 2AKT40A

  • Corrects the display of characters in older DOS applications on non-English systems
  • Fixes a problem where the system constantly reboots in a loop with a Hitachi and Western Digital drive combination
  • Adds fan control to increase fan speed if the processor Voltage Regulator is over 70C
  • Adds an Intel errata patch for the microprocessor firmware to address a potential issue that might cause a system to exhibit erratic behavior such as a system hang, reboot, blue screen, or Kernel Panic in Linux, and may also cause in-progress system operations (e.g., file, I/O) to fail. The possibility of this behavior is believed to be limited, but IBM strongly recommends that customers install this update as soon as possible to prevent the possibility of the issues listed above.

    See Retain Tip H181898 for more details on this issue.
    The IDs of the affected microprocessors are 0F29, 0F33, and 0F34.

    Note: If you want to apply this processor patch without updating the rest of BIOS, refer to the "FLASHING BACK TO AN OLDER LEVEL OF BIOS" topic in the README.1ST file contained in this BIOS update package

    Determining the processor ID
    There are several ways to determine the ID of the processor:
    1. Go to BIOS setup (hold down the F1 key and power up the system) and look under the "Advanced" tab. (The processor ID is about 1/2 way down the screen.)
    2. Use the Microsoft "System Information" tool. Go to the task bar and click through the following selections:
      Click Start, select Programs, select Accessories, select System Tools, then click System Information.

      The first screen displayed with this tool has processor information.
      For example, a F24 ID processor will have the following entry.
      (The "F" is translated to a "15" by this tool.)
      "Processor x86 Family 15 Model 2 Stepping 4 GenuineIntel .."
    3. DMI information. The processor ID is presented in the DMI (Desktop Management Interface) Type 4 structure. There are various tools (DMI browsers) available to view this information.
    4. If you have a Windows installation that for some reason does not have the "System Information" tool, a utility to display the processor ID can be obtained from Intel at the following URL:
    5. System administrators may wish to refer to the following URL for an example of a Microsoft script file that extracts (among other things) the processor ID:

version 2AKT39A

  • Fixes a violation of the USB 1.1 specification for Reset Recovery Time
  • Corrects the display of accented characters in some languages at runtime. For example, the boot password prompt.
  • Fixes a problem where BIOS ACPI IRQ 10 or 11 causes Windows XP to hang
  • Fixes SMBIOS structure 24 information about passwords

version 2AKT38A

  • Fixes a problem where pressing F12 causes the system to boot to the PreDesktop Area
  • Adds a feature so that if the processor temperature is above 65 degrees C at the beginning of POST (indicating a very fast temperature rise), the fans are set to 50% instead of 20%
  • Adds microcode for Intel Prescott 0F34 (D-1) processor
  • Fixes a problem where pressing the Enter key, followed by a 2nd Enter key to pause, followed by F1 does not enter setup as expected

version 2AKT37A

  • Fixes a problem where the mouse moves erratically in Microsoft Windows NT 4.0 by flushing the keyboard controller output buffer on resume from Advanced Power Management (APM) standby
  • Fixes a problem in WinPhlash that causes error "-151" (Unable to find part ID)

version 2AKT36A

  • Adds new SMI function
  • Adds the D-0 processor patch to the flash diskette
  • Fixes a problem where a system may intermittently hang during the memory test of the Enhanced Power On Self Test (POST)

version 2AKT35A

  • Fixes a problem where a system loses of time during APM standby under Windows NT4 and DOS
  • Fixes a problem where a system with a ScrollPoint II PS/2 mouse hangs at TP52
  • Updates the thermal control for Intel Prescott processors
  • Fixes a problem that occurs when performing a BIOS flash update from Remote Deployment Manager (RDM) 4.1

version 2AKT34A

  • Fixes a problem where USB port 6 and port 7 are not available in BIOS 33A (applies only to ThinkCentre A50 and S50 systems)

version 2AKT33A

  • Fixes a problem where the front USB ports do not disable. Due to a hardware limitation in the S50 product, the front ports can only be disabled by disabling all USB. The M50 and A50 products will display the setup question.
  • Fixes a persistent 1762 (number of hard disk drives has changed) POST error when startup "Power On Self Test" = Enhanced and four hard disk drives are present. (If your system is displaying 1762 or 0162, you must clear the errors by entering Setup and selecting "Save Settings And Exit" either before or after upgrading the BIOS).

version 2AKT32A

  • Fixes a problem with boot block recovery with H-L GSA-4040B DVD+RW drive (requires bootblock update)
  • Fixes a problem where there is no video after standby/resume with a USB RAK3 keyboard
  • Fixes a problem where Wake On LAN does not boot to the automatic startup sequence
  • Updates Machine Type/Model table
  • Provides a new version of the onboard Gigabit Ethernet (GE v1.2.16p1)

version 2AKT31A

  • Fixes boot block recovery with some CD-RW drives (requires bootblock update)
  • Fixes boot block recovery with new revision of Teac USB floppy drive (requires bootblock update)
  • Adds setup question to enable or disable the front USB ports
  • Improves efficiency of PCI memory allocation to take up less overall address space
  • Fixes POST hang when PATA is Disabled and SATA is Native
  • Fixes 1805 POST error with certain old PCI cards

version 2AKT29A

  • Fixes a problem where the CGA font is not found
  • Fixes a problem where POST HotKeys may not by recognized with POV systems
  • Fixes an ethernet failure by resetting the ethernet controller on normal (S4/S5) powerup

version 2AKT28A

  • This was an internal release. Any changes will be documented in a future release.

version 2AKT27A

  • Fixes a problem where Ethernet fails with POV and Serial ATA (SATA) in native mode

version 2AKT26A

  • Fixes a problem where a SCSI device stalls the system
  • Fixes a problem where the Admin password is required when booting from a CD
  • Fixes a problem that occurs when performing a boot block recovery with an IDE optical device and a USB floppy (requires bootblock update)
    Note: This BIOS contains Memory Reference Code version 1.3 and GMCH BIOS Spec Update 1.4

version 2AKT25A

  • Fixes intermittent failures booting from a USB floppy diskette drive
  • Fixes a problem where the system will not boot with 4 hard disk drives
  • Fixes hang that occurs with the Intel USB Wireless Ethernet adapter
  • Adds a new 1GB Ethernet option ROM, "Intel(R) Boot Agent GE v1.2.16"
  • Fixes intermittent SATA drive failures that occur during S3 resume

version 2AKT24A

  • Fixes "Power LED not on during bootblock/Clear CMOS state"
  • Fixes "When restoring AC power, system always auto-power on"

version 2AKT23A

  • Rerelease of BIOS 22A

version 2AKT22A

  • Clears the keyboard buffer in function "Boot to PSA"
  • Fixes "System halt when install memory 3.5GB"
  • Fixes "Video adaptors (AGP and PCI) hang system in POST with 4GB"

version 2AKT21A

  • Adds 3.2GHz string for CPU speed reporting in setup
  • Fixes problem of not booting to certain USB floppy drives by increasing cold seek timeout
  • Changes behavior of PS/2 Mouse setup question. Used to be Disabled/Enabled, automatically fixed up based on presence. Now Disabled/Auto/Enabled, where Auto is like old Enabled and Enabled stays enabled no matter what.
  • Adds new 1GB LAN option ROM: "GE v1.2.10p1", which fixes problem with Wake on LAN after PXE boot

version 2AKT20A

  • Fixes Windows 98 USB mouse/keyboard hang after S1 and S3
  • Firstware: Fixes potential issue accessing 48-bit LBA drives
  • Thermal profile update (1-degree resolution)
  • Revised microcode update for 0F29 processor
  • Intel 865G BIOS Spec Update 1.3 erratum #2 (for CKE glitch on S3 entry)

version 2AKT19A

  • Optimizes temperature/acoustics for 3.06GHz CPU
  • Corrects video shared memory setup to show correct amount of memory used

version 2AKT18A

  • Initial Production Release

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Country Availability
Document ID : HT035989
Legacy Document ID : MIGR-60538
Last Updated :
Copyright © Lenovo 2013, all rights reserved
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