By Katie Marsal

Published: 11:00 AM EST

Apple, Dell, and HP notebook customers are banding together in an effort to gain class-action status on a combined lawsuit against Nvidia, which could potentially force the graphics chip maker to replace or compensate for faulty graphics processors in millions of computers.

Five plaintiffs are reportedly leading the charge [PDF], spearheaded by Louisiana resident Todd Feinstein, who purchased a MacBook Pro last April only to find that it "operates at excessively hot temperatures, has a screen which is fuzzy and displays only grey or black at certain times, and periodically shuts down entirely without warning."

Last July, Nvidia informed the Securities and Exchange Commission that it would incur a $150 million to $200 million charge to cover repair and replacement expenses resulting from "a weak die/packaging material set" in certain versions of its previous MCP and GPU products employed by various notebook vendors.

"The previous generation MCP and GPU products that are impacted were included in a number of notebook products that were shipped and sold in significant quantities," the chipmaker told the Commission. "Certain notebook configurations of these MCP and GPU products are failing in the field at higher than normal rates."

In a support document published in October, Apple claims to have contacted Nvidia in July only to be assured by the chipmaker "that Mac computers with these graphics processors were not affected." However, Apple went on to say that its own internal investigation determined that some MacBook Pro computers with the NVIDIA GeForce 8600M GT graphics processor are likely affected.

"If the NVIDIA graphics processor in your MacBook Pro has failed, or fails within two years of the original date of purchase, a repair will be done free of charge, even if your MacBook Pro is out of warranty," the company said.

As ComputerWorld points out, Dell and HP later offered its own notebook customers similar extended warranties but first issued BIOS updates designed by Nvidia that attempted to mask the issue increasing fan speed to help the chips run cooler.

"This is a grossly inadequate 'remedy,' as it results in additional manifest defects, including, without limitation, further degraded battery life, system performance and increased noise in the Class Computers," the plaintiffs using non-Apple systems wrote in the suit. " Worse, this 'remedy' fails to solve the actual problem. Instead, this measure only ensures that the Class Computers will fail after the OEM’s express warranty period expires, potentially leaving consumers with a defective computer and no immediate recourse."

Exactly why the plaintiffs are pressing forward with their suit against Nvidia in light of extended warranty plans from PC makers isn't entirely clear. One explanation may be that they believe the problems plaguing the graphics chips are inherent to past and current Nvidia graphics chips designs, which could lead to repeat issues even with replacement chips.

Following its own investigation into the matter last December, British technology tabloid the Inquirer stated boldly that the dedicated NVIDIA 9600M GT graphics chips in Apple's current unibody MacBook Pros use the same non-eutectic solder contact bumps (or bad bumps) as the GeForce 8400M and 8600M family of chips found in earlier models.

For its part, NVIDIA has vehemently denied the assessment, claiming that the "GeForce 9600 GPU in the MacBook Pro does not have bad bumps. The material set (combination of underfill and bump) that is being used is similar to the material set that has been shipped in 100s of millions of chipsets by the world's largest semiconductor company."