The Pentium flaw has had a powerful effect on the majors operating in the mass market, and Microsoft Corp yesterday delivered a shock announcement that Windows95 may not now be available until August. It says urbanely that the second beta release of Windows95 has been shipped to over 48,000 beta testers and the testing programme will be expanded in the spring to several hundred thousand customers. It adds that feedback from current beta testers has been excellent, and declares airily that given the sheer breadth of Windows95, shipping it may take longer than originally anticipated. The announcement is a bigger setback than it appears, because it makes it more likely that the ship date will slip yet again, and would appear to conceal significant problems. It is also an encouragement to Apple Computer Inc to pull out all the stops on pushing Power Macs and licensing Mac OS.