An AMD representative denied any substantial architectural tweaks of AMD Athlon 64 processors manufactured 90nm fabrication technology on Monday, rejecting the rumors about higher performance of AMD64 parts produced using more advanced process technology compared to 130nm parts.

“There have been no significant changes to processor design between 130nm and 90nm. So expect AMD Athlon 64 3500+ 90nm to perform the same as an AMD Athlon 64 3500+ 130nm part,” an AMD spokesman told X-bit labs.

Earlier this year a report at a web-site claimed the new AMD Athlon 64 3500+ processors made using 90nm fabrication process had scored about 5% faster than the same 3500+ chips produced using 130nm process technology in CPUMark99 benchmark. The benchmark measures CPU integer unit and data processing speeds. Another benchmark the web-site had posted, SiSoft’s Sandra, showcased that the forthcoming AMD64 chips are approximately as fast as the current offerings. Unfortunately, conditions of the testing were not completely clear.

According to AMD’s web-site, the company’s lineup of 64-bit desktop processors include chips that are made using 90nm Silicon-on-Insulator process technology. Currently the company lists there microprocessors rated at 3800+, 3700+ 3500+, 3400+, 3200+ and 3000+ for Socket 754 and Socket 939 infrastructure. Such chips function from 1.80GHz to 2.40GHz clock-speeds.

A recently unveiled roadmap of the Sunnyvale, California-based chipmaker indicated plans to release a number of AMD Opteron processors code-named Athens, Troy and Venus, a Mobile Athlon 64 processor known as Oakville and a desktop Athlon 64 processor code-named Winchester produced using 90nm fabrication process in the second half of the year. The initial commercial shipments of AMD64 chips produced at 90nm nodes were officially said to commence in the third quarter of 2004.

AMD officially announced it had begun shipments of 90nm mobile products to customers, but did not reveal when it planned to supply 90nm desktop SKUs.