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I've formatted my notebook that has a 5400RPM HDD with ~500GB capacity.

After installing Windows 7 and about half the drivers (including chipset) I began to doubt whether to go for IDE or AHCI mode for my hard drive. There used to be a lot of discussion on the internet which is better and so far I understood it was particularly helpful on SSDs. Now the general consensus seems to be that AHCI mode is best for most hard drives. I have thus enabled AHCI in the middle of configuring my notebook (rest of the drivers, necessary software etc...)

Two questions:

  1. considering my HDD's spec above, should I leave it on?
  2. Is there any disadvantage of enabling it after Windows 7 and chipset drivers installation?

Windows 7 version is 64 bit Home Premium.

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up vote 1 down vote accepted

Should I leave on AHCI?

Yes. It allows you to access hard drive performance features IDE simply doesn't have.

Is there any disadvantage to switching after Windows 7 and chipset drivers installation?

YES. Tweaking this after install, while possible, must be very carefully done, potentially requires many windows registry changes, depends on your chipset, and I, as a long time power user, have managed to make a system un-bootable doing it.

As far as I'm concerned, there is absolutely no reason to use IDE mode unless your hard drive or motherboard simply doesn't support AHCI.

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One registry change, that's it... Performance is great and OS is perfectly stable. The amount of dramaticness in your answer makes it almost sarcastic. One registry key needed changing. How "careful" can you be with changing one key and one BIOS setting. You claim to be a long time power user, yet you didn't know how to revert the setting and make windows bootable? Sorry but that doesn't help towards the credibility of your answer... – MDeSchaepmeester Sep 25 '12 at 17:10
Excuse me. Potentially. I forgot the word potentially. The source of that particular anecdote was a lenovo laptop where a combination of lenovo settings in their OEM windows 7 install and conflicts with intel rapid start caused quite the registry c**********k to fix. Only changing HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\msahci caused windows not to boot. I know how to revert settings, and did so. How is that at all relevant to explaining why there is no reason to muck around with IDE these days unless you have hardware problems? – EntropyWins Sep 25 '12 at 19:01
That said, I target answers for the average googler. For them, having to muck about with the bios and registry IS a disadvantage to choosing a legacy HD protocol if the have questions when installing the OS. – EntropyWins Sep 25 '12 at 19:03
I understand now. For me it seems to work fine, as it does for many other users. – MDeSchaepmeester Sep 25 '12 at 20:11

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