"We realize that there is a performance issue based on Microsoft internal testing," said Steve Tobak, vice president of marketing at Cyrix.
Cyrix has been striving to become a major competitor to Intel, but the admission that its chip's performance can't compete for the latest Microsoft operating system could have a major impact on the company's ability to win major corporate customers.
"This basically knocks them out of the running for Windows NT," said Michael Slater, publisher of the Sebastopol, California-based Microprocessor Report.
The problem stemmed from an effort to gain stability and reliability on the new platform. Late betas of the operating system indicated a reliability problem running on Cyrix-based machines. Microsoft rectified the problem with new code inserted into the final release of the software, but the "fix" caused a slowdown of as much as 25 percent compared to the chip's typical performance, Tobak conceded.
Although all 6x86 processors shipped to date have the flaw, Cyrix said they now have a new version of the 6x86 processor, albeit still in the evaluation process, that fixes the problem.
Another front also brought bad news to the chipmaker today. Cyrix acknowledged that, in some cases, third parties are taking IBM processors based on the Cyrix design and relabeling them as Cyrix processors. When these chips are relabeled, they may, in some cases, be marked as having clock speeds faster than the design intended--something referred to as "up-binning"--which leads to potential reliability problems. For example, a P133 processor could be falsely relabled as a P150 processor.
The problem is not unique to Cyrix; Intel has also had this problem with third-party companies in the past. But Cyrix is admitting to the problem just as it is being hammered for the NT performance problems, and because its chips are reported to run too hot and therefore may be unreliable.
Cyrix vehemently denies this last accusation, stating that if PC vendors adhere to the company's specifications, heat and reliability problems would not occur.
Slater confirmed that Cyrix chips do run hotter than Intel processors but added that only improperly designed systems could create reliability problems. However, some low-quality, third-party motherboard and system vendors do not design systems strictly enough to Cyrix specifications, Slater said. Thus, reported symptoms could be true, even if Cyrix can't be held responsible.
NT going slowly on Cyrix