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Hello,
I recently flashed my BIOS to go to v1.02 (which is not the most recent, but all I needed). I even used the EzWinFlash utility to do it, got the "Flash Successful" message, thought I was good to go.
Since the flash, Windows will not load after POST. Everything appears to be normal to that point, the BIOS welcome screen even shows the new BIOS version, drives are detected, CPU and RAM detected, but after all of this, I got the error "CMOS Checksum error - Defaults loaded. I continued from here, and it simply goes to a black screen with the cursor in the upper left corner, does not respond to any commands.
Worse that this, I cannot boot from CD, floppy, USB or HDD. I have tried changing boot sequence, hit about every key during the POST I can think of to try to force boot from CD, nothing is working. I have confirmed that I can in fact access the CD drive by pushing the eject button, so there is power and again, the drive is showing during POST. I load a CD in, the tray closes...and that's it. It will not spin. I have no idea why not. I have also reset the CMOS jumpers and removed/replaced the battery, same issue. When the BIOS settings get reset doing this, I get the Checksum again, but that's it.
I am absolutely stumped. There is obviously wrong with the BIOS at this point and I am wondering if anyone out there has a thought or idea on how I might be able to reflash this thing back to the original version. I have a floppy boot ready to go (found a great article on how to do it), but without being able to get it to boot, it's pretty useless.
Any offerings or insight would be greatly appreciated. Short of a new BIOS chip or board, is there anything left for me to try to at least get this thing to boot into DOS?
Thanks for looking.

Go into the BIOS Setup (usually done by pressing DEL or F10 or another key it might tell you to press at the bottom of the screen during the post messages) and check ALL of the settings to make sure they are set right. If you don't know what the correct settings are, see if it tells you a certain key to press to "Load Optimized Settings" or "Load fail-safe Settings". Hope this helps,
-Trent
"If at first you don't succeed, skydiving may not be for you."
-Our tour guide at Fenway Park in Boston, MA.

Trent is correct. You MUST enter the BIOS immediately after flashing the BIOS to reset values as required.

Just to add, flashing the BIOS is risky business...even moreso if you perform the update from within Windows. If you must flash the BIOS, it's better to do it from DOS using a bootable floppy. Also, why wouldn't you flash to the latest BIOS version available?

I went into the BIOS settings and for each page, I was able to select F6, which allows me to set the entire page to default settings. I've done this for each page and then F10 to save them all before closing out, and the result is the same. I just can't figure out what is going on, and I can't seem to go any further to try and fix it. Very frustrating to be sure.
I appreciate the responses. If anyone might have any other ideas, I'm open to just about anything at this point.

It seems to me that the only option might be a bios chip replacement.
Fix a flash problem
-------------------
www.badflash.com
www.flashbios.org
www.mrbios.com

Aegis is probably correct. How many sticks of RAM are you using ? If two, as a long shot, I would try removing one of the sticks of RAM.

"I went into the BIOS settings and for each page"
That's not how it's done. Use the ClearCMOS jumper on the motherboard. Unplug the power cord, move the jumper from the normal to clear position, wait a few seconds, then move it back. Plug in the power cord, boot up, then go immediately into the BIOS & correct the settings.

Well it would seem that a new chip is about all that can be done at this point. I tried the RAM long shot, sadly it just does the same thing (although during POST it does see that I removed one of the sticks).
Thanks for the suggestions and the tips. I'm going to see where I can get a new chip and just do it that way.
Thanks again.

It sounds like you -
- flashed using a bios version for the wrong model,
or - the bios update download was corrupted, but the flash still managed to complete
or - something went wrong while flashing, but the flash still managed to completeSince the flash produced the "Flash Successful" message, there's a good chance there may be nothing wrong with the bios chip, and you MAY have success if you flash it again with the RIGHT, uncorrupted, update.
E.g. If you used the update for the wrong model, if the I/O chip on the mboard is similar but not the same (e.g. a different model made by the same maker), the bios may partially work but can't make some things work because it doesn't have the proper code.
Are you SURE you used the update for the right model?
AOpen lists:
AX4B Pro 533
AX4B-533
AX4B-533 Plus
AX4B-533 Tube
AX4B-533NSometimes - it's possible that - the extra stuff - Pro or Plus or Tube or N in this case - is not printed on the mboard itself.
In that case you have to confirm which one you have - with older mboards you may have to look at the manuals for the different models if you can't find the differences explained on the site anymore.
.....AX4B Pro 533 - no bios 1.02 listed
...AX4B-533
R1.02 8/12/2002
487.0 KB
Checksum D541h
Add USB 2.0 controller Enable / Disable item.
Speed up CPU fan swirling when enter JukeBox.
Upgrade BIOS in DOS, please download :ae102.zip 251KB
......AX4B-533 Plus - DIFFERENT
R1.02 10/21/2002
504.0 KB
Checksum 611Ch
Fixed FSB setting can not be cleared after clean CMOS.
Fixed CPU/PCI ratio can not be set.
Upgrade BIOS in DOS, please download :ape102.zip259KB
.....AX4B-533 Tube - DIFFERENT
(the one with the vacuum tube for the audio?)R1.02 9/19/2002
507.0 KB
Checksum 050Ch
Fixed Multimedia Device can not be detected at random when FSB533 Processor was installed.
Upgared BIOS in DOS, please download : aet102.zip 311KB
.....AX4B-533N - - no bios R1.02 listed
.....The Checksum is listed so that you can use a program to check whether the update download checksum matches the expected checksum - if it doesn't, it's corrupted.
"I even used the EzWinFlash utility to do it,"
Did you use the version included with the download? If you used an older version, it might NOT be able to flash the update properly.
When you see "Upgrade BIOS in Dos" for an update, and don't see that for earlier updates if they are listed, that can mean the original Dos or Windows based flash utility specified for the model, or included on the CD that came with the mboard, will NOT work properly with that update.
.....I'm assuming in the following you actually have the plain AX4B-533 model.
I looked up EZWinFlash - apparently
"There will be an exe file there"...(when you unzip the AOpen update download) with a W followed by a number. This is the EZ winflash program....There will also be a file with the same number as the exe
file and a bin extension without the W."... (that's the bios update itself)..."Just unzip those to a folder and run
the exe file. "
That's, in this case, the Wae102.exe file, and the Ae102.bin file, you get when you un-zip the update download.
The stated Checksum of the update probably applies to Ae102.binIf you have the choice of either a Windows based flash or a Dos bootable flash for your bios update, it is much safer to use the Dos bootable method - if there is anything wrong with Windows, or if something goes wrong in Windows while flashing, or if there is somthing wrong with your hard drive or it's data, you can end up with a trashed bios if you flash in Windows.
In this case there is a Dos update download available - it has ae102.exe, the flash utility, and ae102.bin, the same bios update file.
The stated Checksum of the update probably applies to Ae102.binIf you have, or you get, the manual for your mboard, there may be directions about how to upgrade your bios using a bootable floppy in it.
If not, generically...Make a bootable floppy.
It is VERY important that your flash floppy has no errors on it.I recommend you use Windows to check your floppy using FULL format. FULL format is slower, but will find and exclude from use any previously undetected bad sectors on a floppy, a common problem these days.
In XP, RIGHT click on A: to find Format, DO NOT use the Quick format switch, format the floppy. After the format has finished, RIGHT click on A:, choose Properties - Free Space should be 1,457,664 bytes for an error free floppy. If it is less than that and the floppy is less than about 7 years old, I recommend you don't use it - it will probably get worse. Format another floppy instead.Once you have a floppy that has no bad sectors on it, Format it again, and this time choose Create a MSDos startup disk
.......Then - copy the extracted files that were in the download, or unzip the files in the download to the floppy - ae102.exe, the flash utility, and ae102.bin, the bios update file.
It is a very good idea to make sure the checksum of the update, probably ae102.bin, is correct BEFORE you flash.
Boot the computer with the prepared floppy.
Type: ae102 , press Enter.
If it does not find the update automatically, type: ae102.bin for the name of the file.
DO NOT select flashing the boot block.
You can save a copy of the present bios to the floppy if you like.
Flash the bios - DO NOT interrupt the process. This method of flashing can be SLOW - if you don't see a message "Flash Successful" or simlar within 5 minutes or so, WAIT at least a few minutes after the last time the floppy led flashes, then reboot the computer.
When you see the "Cmos Checksum error..." or similar message, go into the bios, correct the time and date, load bios defaults, save bios settings, reboot.
.....If you try either method of flashing the bios again and it doesn't help but you still have a bios...
There is a download on the AOpen in the Downloads for model -
Downloads - page 3Utility
EzRestore/ProMagic Utility V60.00.66 8/18/2002
2416.0 KBThat may help - there may be directions about that in your manual, or on the AOPen web site.
....If you try either method of flashing the bios again and it is NOT successful, and the mboard will not boot when you reboot, then see aegis's response 5
In addition...
http://www.badflash.com has a more economical solution, and has the most t-shooting information. He supplies a new chip with the latest manufacturer's update - you MUST point him to the CORRECT bios update.Some sites have only bios Upgrades - that usually costs more, but the bios version has all the possible features and bios bugs removed applicable for your mboard chipset.

Did you have the computer unplugged when clearing the CMOS? That is necessary in order to successfully clear it.

Tubesandwires: Thanks for the extensive post. Here are the answers:
It is an AX4B-533. The end. No tube, R, Pro or anything else. The BIOS version you mentioned there is in fact the one I got and I used the utility that came in the zip file that I downloaded.
The rest of the post is very informative, but again, I cannot boot. From any drive, HDD or any other method I have tried (including making a bootable USB, booting right from the Windows CD and booting from a floppy containing files from bootdisk.com). It just won't boot. So I can't get to those solution attempts, as they all require that I boot into either Windows or DOS, and I can't do either from HDD or disk, as it won't go past the black screen.
I did follow the CMOS jumper instructions to reset from my owners' manual (God knows why I still had it, but I did thankfully) and the computer was unplugged when I reset the jumpers. Still no dice.
Again, I thank everyone for looking. I have decided to just forget this machine, harvest what I can from it and get a new box.
But believe me, I'll be following the "if it ain't broke, don't fix it" motto from now on. Lesson learned.

I still don't understand why you would only update to R1.02 when the latest available is R1.11? I just downloaded it & had a look...apparently there is no option to flash from DOS. IMO, Winflash is never the way to go. Looking at the specs, the board uses an Award BIOS...I'm sure a flash utility *could* have been used with the .BIN file. If you can get it to boot off a floppy, you have nothing to lose.
http://usa.aopen.com/products_detai...

I missed noticing a few things you said that might point to something else.
" I load a CD in, the tray closes...and that's it. It will not spin. I have no idea why not."
An optical drive's basic functions only require the power connection and the computer to be running in order for the tray to be able to open and close and the disk to be able to spin. It doesn't require a working bios, or a data cable connection. When you insert a disk and retract the tray, the led on the front of the drive should come on, and the disk should spin for a short time, even when the data cable isn't connected.
You could try disconnecting the data cable from it, but the symptoms will probably be the same.
If the led on the front of it does NOT light up when you retract the tray with a disk in it, either the drive is not getting the power it needs, or the optical drive is defective.
If the led lights up, but the disk does not spin
- a very common thing - the sleeve bearings in the motor on optical drives deteriorate over time and develop a lot more friction in them, and eventually the motor cannot spin fast enough to acheive even 1X speed (the orginal audio CD standard) or the motor seizes - cannot even start to spin because the friction is too great. This is the main reason no optical drive has been warrantied for more than a year since a long while ago. In that case, the led may stay on longer than normal, and/or go on and off for a longer period than normal.
- a lot less likely, the board on the drive is defective, or has been damaged, usually by an event external to it e.g. your power supply produced too much of what was supposed to be accurate 5v or shorted, or your system experienced a power spike or surge.
Sometimes, when the board is defective or damaged, your computer may not work correctly unless you disconnect the data cable from the drive, and possibly its power connection too.
- the power supply may be failing - this is VERY common - the optical drive requires both accurate 5v and 12v - if either of those are too high, too low, or not present, the optical drive will not work properly or will not work at all.
If the 5v is too low your optical drives, floppy drive, PS/2 devices, serial devices, and USB will not work properly - if the 5v is not present none of those will work at all.Hard drives require both 5v and 12v too, but I have personally seen AT computers that still booted and the fans and hard drives spun fine, and the hard drives worked on, despite the PS not putting out any 5v.....
"I cannot boot from CD, floppy, USB or HDD"
..... but that may not be possible if there is no 5v for ATX computers, which is what virtually all computers since about 2001, and yours, are/is.
So....
- try the optical drive connected to another known good working computer if you can - if it doesn't work on that one, either the drive motor is not spinning, or, a lot less likely, the board on the optical drive has been damaged, e.g. by your power supply producing too much of what is supposed to be accurate 5v, or shorting.
- Failing power supplies are common and can cause your symptoms.
Check your PS.
They often partially work, fans and hard drives spin, leds come on, yet you may get no video and the mboard will not boot all the way.
See response 4 in this:
http://www.computing.net/hardware/w...If you can try the PS with a known working computer, or if you have a spare PS with enough capacity, or can temporarily borrow one to try with this computer, do that, rather than risking buying a new one - you don't necessarily need to remove the present PS - just prop up the one you try next to the case and connect its wiring.
.....
By the way, if you are using a video card (in a slot) with this, which one are you using?
The original PS in your system may not have enough wattage capacity / 5v and/or 12v current capacity to handle a card with a recent video chipset, and using such a card will eventually fry an inadequate PS.
......
Your bios may work fine if there is one of those things wrong with your system and you cure the problem, but if the original PS is no good, you may need to flash it again.

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