PC enthusiasts looking to grab an early copy of Windows XP may be in for a big surprise: many will need more computing horsepower to run the operating system. Microsoft on Monday released the second test version of the new version of Windows, also launching a preview version for the public. But those spending $19.95 (£13.91) for the preview may be forced to buy additional memory or upgrade their processor to run the software. Microsoft's Web site recommends a minimum 300MHz Pentium II processor and 128MB of RAM to run the Windows XP beta, up from a 133MHz processor and 64MB of memory for Windows 2000. Although many PCs come with 128MB now, machines sold a year ago, especially budget PCs, typically came with much less memory. Analysts warn that the requirements could force many early adopters to buy new PCs to run the new commercial-consumer operating system. At the least, many will have to beef up their PC's memory. While the system requirements could change before Windows XP's release later this year, analysts say they would more likely go up than down. According to market researcher Metafacts 58 percent of desktops and 60 percent of notebooks in use in the United States have 64MB of memory. Systems packing 128MB or more account for only 21 percent of desktops and 19 percent of notebooks. The problem is further exacerbated by Microsoft's history of understating the actual system requirements required for new operating systems, say analysts. Last year’s Windows 2000 release, for example, necessitated massive memory upgrades and compelled many companies to replace systems before switching from Windows 95, 98 or NT. Based on Microsoft's recommendations, only a small number of PCs should have required an upgrade. "Microsoft tends to downplay what you need, and the reason they are doing that is investors," said ARS analyst Matt Sargent. "We went through this whole thing with Windows 95, where they looked at the installed base and said the requirements are very low." Lower system requirements increase the pool of those using existing Windows versions who will consider upgrading to the new operating system, something Microsoft wants to strongly communicate to the financial community, Sargent said. "They're trying to increase the potential installed base for upgrades." Gartner analyst David Smith agreed that Microsoft tends to be "overly conservative". But he felt Microsoft had other reasons for its hardware recommendations. "The requirements going up so much are quite surprising," he said. "I think they're looking at the demographics out there and what they want to support." But Microsoft has actually released a second set of minimum hardware specifications, said Art Pettigrue, the company's Windows product manager. Those suggest a 233MHz Pentium II processor and 64MB of RAM. "There are two guides out there right now. The first is for core technology and the other is for the best experience you might have running Windows XP," Pettigrue said. While he emphasised "nothing is final", and the "requirements could change before final release," Pettigrue said the lower requirements are "the minimum for the typical user". IDC analyst Roger Kay, who is running a Windows XP beta, disagreed. "The minimum requirements talk about putting the operating system on your hardware and nothing else," he said. "If you want a computer that actually works, you need much more hardware than that." Sargent agreed. "The specs they list are typically well below what makes sense for the computer." An interesting proof point is test systems Microsoft has dispatched to some analysts. The Windows XP Beta 2 test PCs typically come with the fastest processors available and 320MB of RAM. When released, Windows XP will come in two flavours: Home Edition for consumers and Professional for businesses. But the important difference from older Windows version is significant. Microsoft is releasing its first combined consumer-business operating system using the same codebase. Windows 95, 98 and Me share a common heritage with DOS and Windows 3.1, while the business-oriented Windows 2000 is based on Windows NT. Microsoft has not released final pricing for Windows XP, which could be affected by whether the company includes subscription services, Smith said. "They haven't decided about this yet," he added. The company has added many new features to the second beta, including the Luna interface, which bears striking similarity to Microsoft's MSN Explorer. Windows XP also sports lots of multimedia extras, such as sophisticated movie editing and production tools, a Web publisher, built-in support for CD-rewritable drives and DVD playback, among other things. "The difference between Windows 2000 and Windows XP is largely cosmetic," Smith said. "There's no new kernel, no new memory management system, and the guts are the same." The real payback would be for consumers, who would get the most stable operating system Microsoft has offered along with better ability to run multiple programs simultaneously. Those added features and the Luna interface could be leading reasons for the heftier system requirements, said MicroDesign Resources analyst Peter Glaskowsky. "Fundamentally, the user interface is a lot more sophisticated, and there are a lot more things going on behind the scenes for managing disk drives and that sort of thing," he said. "Any time you increase the number of graphics you have to process, you increase the amount of background tasks going on. So you just naturally have to have a faster CPU, and more memory is almost definitive with a faster CPU." But Glaskowsky is less concerned with system requirements, noting no one really sells 233MHz or 300MHz processors anymore. "Microsoft has said Windows XP is intended for hardware after 1998," he added. "That's about right. That was the 300MHz generation." The larger issue may be whether people move up to Windows XP and keep existing hardware. Pettigrue said he upgraded to Windows XP beta from Windows Me on his home machine, which meets the 233MHz Pentium II and 64MB of RAM requirements. "I'm not doing anything power-user-like," he said. "I'm using it as my mom would use it." His work machine, with a 500MHz Pentium III processor and more memory, is being used for more demanding tasks Microsoft expects from power users. But Kay said he sees 500MHz processors as a more reasonable minimum for Windows XP. "You're going to need a lot of hardware to run this," he said. Take me to ZDNet Enterprise Have your say instantly, and see what others have said. Click on the TalkBack button and go to the Microsoft forum. Let the editors know what you think in the Mailroom. And read what others have said.