AHCI worth enabling?

eaglenest

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Just built a system and don't plan on using more than one hd and won't need hot swap. Would there be any significant advantage to enable AHCI mode in the BIOS ? If I do enable it, are there any disadvantages I should be aware of? I have Western Digital Sata HD, a gigabyte mb, and an AMD Phenom processor. Have not installed the OS yet. Will be using Windows7.
System will be used for general purpose and some light to moderate gaming and graphics applications
Thanks.
 
Yep, it is pretty easy to do with Win7 as Win7 already has the AHCI driver. I think it has some minor speed improvements as well. The only downside I have seen is when doing "safely remove hardware", be careful not to remove your hard drive (as it will show up there now). No idea what would happen if you tried to, I imagine it would tell you the disk is in use and that is not possible.
 
Running in AHCI mode can/will help with random read/write performance and therefore responsiveness. As EXT pointed out, Windows 7 includes the necessary drivers. However, to speed start up times Win 7 only loads the drivers it's told - (by the Bios at install time) - are necessary. So, if you merely pop into the Bios and flip the AHCI switch to 'On', you'll get the "Windows Has Failed To Start" troubleshooting sequence instead of getting into your computer.


In technical circles, that's known as "A Really Bad Thing", and we try very hard to make sure that never happens.



But we're smarter than that, and will make the proper registry entries in Windows before screwing with it... THEN shut down; pop into the Bios on the way back in to make the change; let Windows load; and - because we've made a fundamental alteration to the system - restart once Windows has completed it's work.

And because we here at Toms are smart, we also know very well that monkey~ing around with the Windows Registry has the potential to brick your OS. So we double check that we're making the proper entries; that we are making *only* the proper entries; and we are positive we're not touching anything else.




So - Yes, it is possible to enable AHCI after the fact... If you want to....

Warning:

BACK UP YO SHEEYAT!!!

THIS INVOLVES REGISTRY SETTINGS!!

THE ONLY ONE RESPONSIBLE IF YOU DO THIS IS YOU!

MAKE A SYSTEM RESTORE!!

IT'S THE RED PILL!!! OR WAS IT THE BLUE?? No... Wait....



oNE sIDE mAKES yOU bIG... thE oTHER sIDE... Aaaahhh... screw it: Here's the Tutorial.
 

eaglenest

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Thanks for your amusing and informative answer






 

eaglenest

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Thanks.


 

becherovka

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The only reason not to use it is if it on your dvd drive as well, it slowed mine to half speed (dont exactly know why). I have changed it so it is enabled only on hard drive seems to work well.

PS to do this i had to plug SATA cable into different slot, guess it depends on you mb if you can do this.
 

jonathan7007

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Becherkova,
Did you mean that to keep the DVD drive as an IDE drive you:

1. took all steps to switch system to ACHI
2. switched SATA cable from DVD drive to a different SATA connector on the mobo
3. booted and did NOT have to make any changes in the BIOS
4. DVD ran better. Faster? fewer coasters?

Which mobo? I have a Gigabyte X58A-3UDR

jonathan7007
 

becherovka

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Did you mean that to keep the DVD drive as an IDE drive you:

1. took all steps to switch system to ACHI
2 tested dvd drive took twice as long to copy a dvd
3. switched SATA cable from DVD drive to a different SATA connector on the mobo port 4/5 or under different controller.
4. booted and changed dvd drive back to ide, while leaving hard drive ACHI. (port 4/5 as standard IDE in my bios settings)
5. tested dvd drive back to normal speeds.

My MB - GA-ma785-UD3H - has 6 SATA ports with two under separate control to the others, put dvd in one of these.

Your MB has 10 SATA on three different chips. Should be no problem just dont know your bios setting.

Hope this makes sense

PS the port 4/5 will be different on yours.