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I'm trying to understand what an MBR is. I know it is used to boot the device, like a compact flash card.

If you had five 1GB CF card from SanDisk for a camera, would there be any reason for the manufacturer to have different MBRs? It seems like to me, if for some reason one CF card wouldn't boot, you could copy the MBR from a working CF card and write it to the non-working CF card.

Would this MBR for a SanDisk card work on the same size Western Digital card for the same use?


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up vote 2 down vote accepted

You may want to read the Wikipedia article.

A MBR in 5 1GB CF cards will most likely be similar, but it doesn't have to be.

As long as the device is not taking advantage of anything additional (e.g. repartitioned, active partition etc.), it may be possible to straight forward copy across.

However, copying the MBR can be quite complicated, and if you were willing to go to this length, I would advise using a standard recovery tool that scans the media instead of looking at the MBR, and recovering the data, then formatting the card and putting the data back.

As for SanDisk MBR on a WD card (I didn't know WD did flash media?), there is no way to know really - the MBR contains a lot of data about mechanical hard drives - cylinder, sectors etc, so it really depends how similar the cards are. If they are different speed classes, I doubt it. If they are very similar, it could work.

Sorry I am not really more help, but I hope you find some of this interesting.

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More head spinning info on MBRs – Moab Feb 3 '11 at 22:59
@Moab - wow, good find! Will read that site when I have more time! – William Hilsum Feb 7 '11 at 0:38
You are welcome Wil. – Moab Feb 7 '11 at 21:08

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