No floppy after CPU Swap/ Dead MB

Hot-swapping and Boot-Block flash & Boot block flash and floppy support
Terry Lealos
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ruelnov,

I already TRIED to download that file from Syncmos, but after "download complete" with in a second or two, it said 0 bytes transfered. I tried several times earlier to get it w/ same result, I just tried it off your hotlink, and same thing.
I tried the removal of ALL Ram Modules and got no beep. But if I am understanding my situation correctly, my Bios is corrupted because of improper CPU settings. The Clear CMOS is not getting me back to Checksum Error so I can enter setup. This is where I believed forcing a checksum error was needed because remember I have lights flashing on my keyboard (once) my cd Roms (constant-then off) but my floppy has no light (except when plugged in backwards it will stay constant).
One of you guy's suggested he had the prob once and figured his Bios was shutting down before powering up the floppy, maybe CPU, speaker, Ram etc. and the AMI Bios would be searching for a bootlock but can't get to it with no floppy. Ergo the need for either force checksum error, re-program chip, or replace bios. I hope this is correct?

Lastly to all you guy's helping, you don't realize how much I appreciate your help, not just for the sake of the repair, but because your teaching me alot! THANK YOU!

FYI- This M599LMR board w/ AMI Bios (current) is SUPPOSED to be an "automatic" detection for CPU changes, and I know the last setting I made to the bios in setup was to put it back on auto from user define. Why isn't it automatically detecting my AMD K6 III 450?

Someone asked about the voltage setting I made while running the Cyrix. The Cyrix was running at 2.9 and I lowered it to 2.0 for the new AMD. I shutdown and replaced my CPU w/ AMD then restarted to BLACK---nothing (like now) I shutdown, cleared CMOS w/ jumpers, put Cyrix back in and got checksum error allowing me back into Bios setup. I set to automatic this time and shutdown and swapped back to AMD and got what I have now. Clearing CMOS or all the other things so far have not changed my ability to get back into Bios setup. Hope ALL this helps you guy's......Thanks again..........

One more thing, I tried jumping the 2 end pins with negative result. one of those pins, the end one is the only pin on the chip showing 0 voltage when powered up.
Built a few computers, repaired alot, but still needing to learn.
Terry Lealos
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Hey guys I just got the schematic off the hotlink ruelnov sent. It seems that AOL was stopping the download somehow, I went thru IE and it downloaded correctly. Will let you all know.......
Built a few computers, repaired alot, but still needing to learn.
Terry Lealos
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Tried a17 and WE pin shorted while starting up and after1-2 minutes nothing no beeps or light flashing on floppy. Tried it with both Cyrix and AMD CPU's same result. Next step check/ replace Syncmos chip? Or try shorting other pins? Keep in mind I am still trying to save board.
Built a few computers, repaired alot, but still needing to learn.
ruelnov
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Try shorting other combinations of WE pin and A pins. If still no effect, try any combination of two A pins. But in both cases, make sure that the voltage between the 2 pins you are going to short is zero.

If this doesn't work, then your CPU is really dead, as it did not seek RAM when you remove your RAM modules.
KachiWachi
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You didn't specify in your post (Wed Aug 18, 2004 7:04 pm)...can you still boot with the Cyrix or not?
ruelnov
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He mentioned in his original post that even his Cyrix boots to a blank screen, so it's not booting up and that's why there's no floppy access.

But before we conclude that his CPU's are dead, he should tell us if his CPU fan is turning at power up. If yes, then power is reaching the board and the CPU is really the primary suspect.
Terry Lealos
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Yes the CPU fan starts on power up. No beeps w/ ALL Ram removed. I have tried 12 other CPU's in the board all with no difference. NONE of the CPU's including the Cyrix will boot to checksum error. The Cyrix did the first time I removed the AMD 450 when it failed. I simply removed AMD and cleared CMOS w/ jumpers. put Cyrix CPU in and got to checksum error. I set CPU settings to AUTO and shutdown. To this point all I have tried has NOT got me back to Checksum error screen. I am going to try a USB powered Floppy and see if I can install Bootblock disc with it. Also I am going hunting for a Syncmos Bios so I can try replacing it.
Built a few computers, repaired alot, but still needing to learn.
ruelnov
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The first requirement to recover your system is for the CPU to seek RAM, because if it doesn't then it's not alive.

And if none of the CPU's you have tested so far tried to seek RAM when you powered up without any RAM, there's no point in exploring "USB-powered floppy" or "Syncmos chip replacement". Even forcing a checksum error won't do here. For the simple reason that the CPU itself is not waking up!

These CPU's could come alive in other boards, so I suggest you try this first. And if your Cyrix does come alive in another board, then your problem is on some components in your board that may have got damaged when you did the voltage mod.
ruelnov
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These tricks are also worth trying:
1. Hold down CTRL+HOME, then power up while still holding the keys down. If you get floppy access, then proceed to reflash your BIOS.

Or:
2. Power up, then clear CMOS by moving the jumper to CLEAR POSITION while the system is powered up. Then return jumper to NORMAL POSITION with system still powered up. Wait for system to boot.

The CMOS should be now completely cleared, and the system should be able to boot (granting the problem was with CMOS settings).

I used the second method of clearing my CMOS completely a number of times without problems. This after I realized that the usual method of doing it is not doing the job well.
Ritchie
BIOS Guru
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Something else worth considering:

Disconnect your ATA cables from your drives, and try powering up without them connected.

Because today I borrowed a power connector from an old 8X CD-ROM drive to temporarily slave an old HDD to a newer HDD, and could not understand why the system powered on but with the HDD LED on solid and with no video. Then I also disconnected the P-ATA cable from the CD-ROM drive and tried again, and I had the usual POST. Once I disconnected the temporary HDD and reconnected both data and power to the CD-ROM, the system was happy again to accomodate the CD-ROM drive.
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