Howto fix slow hard drives

If you think that your IDE hard drives are slow you might want to check their transfer mode by going into Control Panel > System > Hardware > Device Manager. Click on IDE ATA / ATAPI Controllers and right click the primary ide channel (and secondary ide channel if you have hard drives there too) and select properties from the menu. Select advanced setttings from the tab and check the setting under current transfer mode. If you see Pio or a low Ultra DMA mode you might want to try the following fix to increase the speed of your drive(s).

Note: You should know the maximum DMA mode value of your hard drive. Windows reduces this value after six read or write errors and will not automatically rise it again. This could mean that your hard drives are running in a lower mode than they are capable of.

Enter the registry and navigate to the following key:

HKEY_LOCAL_MACHINE\SYSTEMCurrentControlSet\Control\
Class\{4D36E96A-E325-11CE-BFC1-08002BE10318}

You find a list of subkeys, e.g. 0001, 0002 aso. Click on them to see their values. To verify that you have located the correct subkey, verify that the DriverDesc value for the subkey contains the string value “Primary IDE Channel” or the string value “Secondary IDE Channel.”

1. Backup your registry right now:
2. Delete MasterIdDataCheckSum and SlaveIdDataCheckSum. This resets the number of read and write errors.
3. Create the Dword ResetErrorCountersOnSuccess and give it the value 1. The transfer mode is only lowered if you have six consecutive read or write errors, before it was cumulative (alltime).
4. Add the value ffffffff to the following keys if they exist:

• MasterDeviceTimingMode
• MasterDeviceTimingModeAllowed
• SlaveDeviceTimingMode
• SlaveDeviceTimingModeAllowed
• UserMasterDeviceTimingModeAllowed
• UserSlaveDeviceTimingModeAllowed

Restart your computer and look in the device manager if you see any changes. This method works well if you have problems playing dvds and you experience a stuttering.

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