Intel is facing another showstopper for PCs using its 820 chip set. The company announced Wednesday morning that it will replace motherboards using its 820 chip set that are exhibiting symptoms of a problem with a related component -- called a memory translator hub, or MTH -- with synchronous dynamic RAM (SDRAM). While the MTH is not part of the 820 itself, it is required on a motherboard that uses SDRAM. It enables the chip set, which was designed to work with Rambus dynamic RAM (RDRAM), to use less expensive, more readily available SDRAM memory. "We have found that some systems ... may be sensitive to system board noise," an Intel spokesman said. Hangs and reboots The MTH problem, which manifests itself in symptoms including system hangs and intermittent system reboots, is due to noise caused by simultaneous switching of signals on the MTH buses, Intel officials said. Intel is working with PC and motherboard makers to notify end users of the issue and to offer a replacement motherboard. Intel plans to replace all the 820 motherboards with SDRAM support it has sold directly to its customers with an Intel 820 chip set motherboard with RDRAM memory. Computer users who believe they are affected should contact their manufacturers. Or they can check Intel's Web site, where they can download the MTH ID Utility to test for the presence of the MTH. The MTH support site, located here, also includes additional information on the problems. "We believe less than 1 million boards with the MTH have been shipped to customers," an Intel spokesman said. However, "since we have determined no root cause on this issue, we have decided to offer a replacement." First noted in November Intel began shipping the MTH last November. The issue was brought to light by an Intel customer, who observed the problem on a "small number" of 820 motherboards with the MTH and SDRAM. Intel followed up on the report and observed the problem in its own tests earlier this month. While Intel works to resolve the problem, the company has halted production of the current MTH for the 820. Intel has also asked motherboard and PC makers to halt shipment of products based on the 820 chip set with the translator hub for use with SDRAM. The company requested the halt to give it time to test and validate a new version of the MTH, with increased resistance to noise. Intel is now working to test and validate the new component. It did not, however, give an estimated ship date for the new component. The 820 is an important chip set for Intel because it is aimed at high-end consumer and corporate systems, where Intel makes the majority of its sales. The chip set was to be the replacement for Intel's 440BX chip set; however, the 820 has been marred by two production delays related to RDRAM. Analysts now believe that a forthcoming chip set, called the 815, will be the chip set that does the most volume as a main-stream desktop PC chip set. Problems with the chip set and SDRAM began to appear last month. Intel, at that point, pointed to SDRAM makers that cut corners in the manufacture of SDRAM memory modules as the cause of the problem. Officials, however, said that problem is unrelated to the current issue and has since been resolved. International Data Corporation figures show that in the first quarter of this year, nearly 80 percent of all 820 chip set motherboards shipped with SDRAM. About half of all 820 motherboards now ship with SDRAM, analysts estimate. The halt will likely not affect large PC makers, such as Dell and Compaq, because those PC makers ship 820 chip set PCs exclusively with RDRAM memory. The halt, instead, will affect smaller PC vendors, such as white box vendors, which may pair the 820 with SDRAM, analysts said. What do you think? Tell the Mailroom. And read what others have said. Take me the CPU Roadmap: AMD vs. Intel