In the spring of 2000 the packaging picture became even more complicated with the announcement of the first Celeron processors derived from Intel’s 0.18-micron Pentium III Coppermine core. These were produced using yet another form factor – Intel’s low-cost FC-PGA (flip-chip pin grid array) packaging. This appeared to mark the beginning of a phasing out of both the PPGA and Slot 1 style of packaging, with subsequent Pentium III chips also supporting the FC-PGA form factor. New Socket 370 motherboards were required to support the new FC-PGA form factor. Pentium III processors in the FC-PGA had two RESET pins, and required VRM 8.4 specifications. Existing Socket 370 motherboards were henceforth referred to as legacy motherboards, while the new 370-pin FC-PGA Socket-370 motherboards were referred to as flexible motherboards.
At the time of its introduction the Coppermine-based Celeron ran at 566MHz. There were a number of speed increments up until 766MHz, at which point the next significant improvement in the Celeron line was introduced. This was in early 2001, when the 800MHz version of the CPU became the first to use a 100MHz FSB. By the time the last Coppermine-based Celeron was released in the autumn of 2001, speeds had reached 1.1GHz.