The move came just days after a Web designer created a site that , including screens broken in shipment, on-again-off-again flickering displays and screens that showed a jaundice-yellow tint.

Two Apple resellers -- independent dealers approved by Apple to sell Macs -- contacted the site to report that all shipments of iMacs had been pushed back at least two weeks as Apple replaces the machines' graphics cards.

Canadian Web designer Scott Pronych built the tracking site after he received a 27-in. iMac with a shattered screen, saying he wanted to document the display problems. By digging through Apple's support forum and taking reports directly from others via a form on his site, Pronych has identified more than 600 users who have had issues with their new machines.

dedicated to the flickering screen problem boasts nearly 1,200 separate messages and has a view count of over 173,000, making it easily the most-read of those on the iMac forum.

The resellers who contacted Pronych are in Europe. "I think they are feeling a bit frustrated as a lot of customers are blaming them for slow delivery, and likely they see my Web site as proof that there are some real problems with the graphics system of the new iMacs," Pronych said in an e-mail Friday.