AMD has been hit with a class action lawsuit following revelations its Bulldozer octa-core chips only used a maximum of four cores at a time.
The lead claimant is Tom Dickey, although he is bringing the on behalf of a number of others as well as himself. The suit claims AMD made false claims when promoting the CPUs, allegedly tricking consumers and businesses into buying hardware that was less powerful than advertised.
The issue rests largely on the architecture of the chips; the 'modular' design adopted by AMD means each core cannot function independently and must work in pairs. However, this fact was not publicly advertised.
"In fact, the Bulldozer chips functionally have only four cores - not eight, as advertised," the claim reads. "Notably, AMD built the Bulldozer processors by stripping away components from two cores and combining what was left to make a single 'module.' But by removing certain components of two cores to make one module, they no longer work independently. As a result, AMD's Bulldozers suffer from material performance degradation and cannot perform eight instructions simultaneously and independently as claimed."
AMD, while it hasn't commented on the lawsuit specifically, denies the claim the modular design leads to performance degredation, saying it has minimal effect.
If Dickey et al are successful, however, the company faces damages of a minimum $5 million (3.3 million).
The case continues in the U.S. District Court For the Northern District of California, San Jose Division, case number 5:15-cv-04922-PSG.
