Acer 930 Bios Manual page 36

Single Processor MP Table
Enabling this parameter allows BIOS to create a multiprocessor (MP) table
for Windows NT use. In a single-processor system running Windows NT,
you may disable this parameter to enhance system performance. If you
install another CPU for a dual (or multiprocessor) system, enable this
parameter then re-install Windows NT.
In cases when this parameter is enabled before installing Windows NT in a
single-processor system, you may upgrade to a multiprocessor system
without reinstalling Windows NT.
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