Replacing BIOS chip on an HP 6550b - any correctly named chip?

Discussion in 'BIOS Mods' started by Tommygunn792, Nov 11, 2015.

  1. Tommygunn792

    Tommygunn792 MDL Novice

    Oct 29, 2015
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    I'm looking to replace the BIOS chip on my HP Probook 6550b laptop. Looking around Ebay they are sold specifically for this purpose at around the £12-15 point, however, can I just buy any chip of the same make/code, at a fraction of the price, and it will do the same job or are the Ebay retailers doing some magic to the chips to make them work?

    Cheers,
    Tom.
     
  2. LatinMcG

    LatinMcG Bios Borker

    Feb 27, 2011
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    #2 LatinMcG, Nov 11, 2015
    Last edited: Nov 14, 2015
    its whats in the chip.. you would need the .bin dump from 6550B and flash it then solder.

    serial and DMi info missing from bios dload.
    likely will need nbdmifit after.
     
  3. Michaela Joy

    Michaela Joy MDL Crazy Lady

    Jul 26, 2012
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    @Tom: You'll have to check the specs of the IC that you are purchasing against the specs of the original part. Read timing as well as write timing. The replacement part needs to be as close to the original part as possible.
    If there's a discrepancy in the bus timing, or R/W setup and hold times, the part will not work.
     
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  4. Tommygunn792

    Tommygunn792 MDL Novice

    Oct 29, 2015
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    Ok, thanks to the both of you for your points, I'll pay the extra and go for a preprogrammed chip in that case.

    Some retailers are stating their 6550b chips are for '68CDE Rom Family' or '68CDF'. What does that mean and how do I choose the correct type?

    Tom.
     
  5. LatinMcG

    LatinMcG Bios Borker

    Feb 27, 2011
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    #5 LatinMcG, Nov 14, 2015
    Last edited: Nov 14, 2015
  6. Tommygunn792

    Tommygunn792 MDL Novice

    Oct 29, 2015
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    LatinMcG,
    I am actually going to buy a chip that is already programmed and ready to go but I need to know which chip to select (CDE or CDF). Are there any identifying markings or features that tells me what my laptop uses?

    Tom.
     
  7. LatinMcG

    LatinMcG Bios Borker

    Feb 27, 2011
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    research the long model number .. post all infos on stickers including serial and we might be able to find out which.
     
  8. Tommygunn792

    Tommygunn792 MDL Novice

    Oct 29, 2015
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    Funnily enough I had actually taken a photo of the computer spec screen a while a go, to record the info just in case, and low and behold it has what I'm after, problem solved. Can't post a photo, not enough posts, but it tells me it is a '69CDE Ver. F.23'

    Thanks for the input everyone.

    Tom.
     
  9. LatinMcG

    LatinMcG Bios Borker

    Feb 27, 2011
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    also if chip is different the flash program might not be able to flash if it cant find one of the chips.. different brand or type.