You can do a Google for "beep codes".
Replacing the MB will not affect HD information.
I lean toward the MB. A visual inspection will not disclose open connections or failed ICs.
I have a Compaq 6420NX AMD ATHLON XP HOME EDITION, 256 MBG memory, 200 Gig drive , 2 gig processor desktop which suffered a meltdown. I was on the phone with COMPAQS tech support for hours with at least four different techs each telling me something different as the cause of my woes: computer will power up but won't start. I get two beeps at the beginning of the power up phase one high pitched beep and then one lower pitch beep. I noticed on the front of the computer two indicator lights: one green and one yellow, the green(motherboard) one normally would come on during power up of the computer and stay on until I turned the computer off, the yellow light (hard drive)would come on and flicker like crazy while the computer initiated its way to the desk top screen. It would then go off or reduce down to a blink now and then until I either activated another program or surfed various site which it would then flicker like crazy again. Without warning recently my computer went crazy and programs started shutting off automatically, then the screen froze and then the computer went into SAFE MODE. I logged back in using NORMAL START UP and everything seemed fine for a moment and then the process began again. I restarted my computer thinking it was some WINDOWS fluke and afterward was unable to restart my computer again. I contacted the tech support where I was told it was the video card (so I purchased another card, but that was not it), then I was told it was the MEMORY so I bought new memory and that didn't help. I then was asked to disassemble,reassemble, check for loose cables, go into BIOS (which I absolutely an unable to do) AND NOTHING WORKED!!! I checked the motherboard to see if a componenet had burned out, but saw nothing. I thought to replace the motherboard, but found out that if I do that my hard drives which contain all of my data won't be recognized and I won't be able to access my data.
First I would like to ask is this TRUE??? and if it is how can I get access to the data I have on my hard drive? WHAT CAN I DO?
I think rather than computer companies wasting so much time on GIMICKS they should focus on such matters as this where if a person's system crashes he can change components within the computer without compatibility issues with the hard drive(s) or worst come to worst, should a person buy another computer he can install his old drives in the new system and continue using the drives and information without losing or losing access to anything.
Any help offered will be appreciated
Thanks

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