The Philadelphia Stock Exchange Semiconductor Index, or SOX, was up 15.4% in midafternoon, spiking sharply on the Fed's rate cut.

Sector bellwether


(INTC) - Get Intel Corporation (INTC) Report

surged and was up 9.1%.

Applied Materials

TheStreet Recommends

(AMAT) - Get Applied Materials, Inc. Report

was up 21.5%.

Other tech indices jumped as well. The

Box Maker Index

was ahead 11.2%. Internet Index

was up 15.3%.