i installed last year my winXP musical stystem using NLite and setting it to PC standard. now i experience some problems with some applications, possibly related to the pc standard installation: CPU spikes, CPU always a 100%, not possible to use multiprocessor engine (which i can use in the other XP installation with multiprocessor PC ACPI) in the main music program (sonar 6, which i updated recently) i'd like to switch from PC standard to PC Multiprocessor ACPI but if i go into the system panel i cannot perform this action. if i choose to install new drivers for the "PC", i cannot find any way to switch to multiprocessor, and no drivers is found on the XP cdrom... even if follow what's written here: http://support.microsoft.com/default.aspx?...kb;en-us;234558 Installing Support for Multiple CPUs1. Click Start, point to Settings, point to Control Panel, and then click System. 2. Click the Hardware tab, and then click Device Manager. 3. Double-click to expand the Computer branch. Note the type of support that you currently have. 4. Double-click the computer type that is listed under the Computer branch, click the Drivers tab, click Update Driver, and then click Next. 5. Click Display a list of known drivers for this device, and then click Show all hardware of this device class. 6. Click the appropriate computer type (do not change from non-ACPI to ACPI computer types), click Next, and then click Finish. on point 5 i am now shown anything beside standard PC do you have any suggestion, beside reinstalling all the system? i can make multiple tries, since i have a ghost backup of the partition... what if i copy the hal.dll file from my "normal installation" (on the other partition with PC multiprocessor) to the "music installation" (with PC standard)? thanks!