Intel said yesterday it would replace computer circuitboards with a defective memory part that have caused some PCs to crash, a move that analysts said could cost the world's largest computer chip maker hundreds of millions of dollars. Intel said the problem arose from a defective memory translator hub, or MTH, component that translates signals from SDRAM (Synchronous Dynamic Random Access Memory) to the Intel 820 chipset. The problem results in "system noise" that causes some systems to suddenly reset, reboot or just stall.