AMD has rebutted allegations that the launch date of its long-awaited Phenom processor has been delayed to Q1 2008 after the chip company fell behind on its original Q4 2007 release schedule.

A DigiTimes report says sources at unnamed motherboard makers maintained the delay is due to AMD's wish to increase the yield rate and frequencies of Phenom processors, in an effort to improve the CPU's competitiveness against Intel's upcoming 45nm 'Penryn' Core 2 Duos and Core 2 Quads.

It was originally thought that AMD was still on track to release four processor models under the Phenom brand during Q4, more specifically around November this year. This was thought to include the Phenom FX-80, the dual-core Phenom X2 GS-6550 and two quad-core Phenom X4s, the GP-7100 and the GP-7000.

Despite the sources claiming that AMD has already contacted several motherboard makers with news that Phenom will begin a test production process between November and December 2007, but not launch until the first quarter of 2008, the chip giant still maintains that its H2 2007 release schedule has not changed.