Washington, January 14:

Microsoft’s new operating system, due to appear on store shelves over the coming weeks, will make some hefty demands on computer hardware.

Conservative estimates from research group Softchoice and others suggest that at least 50 per cent of PCs currently in use do not meet Vista’s minimum system requirements. That figure jumps to over 90 per cent among PCs used in corporations.

The big question facing consumers who want to adopt Vista sooner rather than later is whether it makes more sense to buy a completely new PC or whether individual component upgrades will suffice.

It’s a tough call, considering that upgrading just two or three key parts of your PC — such as the video card and hard drive — can cost about a quarter of the price of a new machine.

At a minimum, says Microsoft, your PC should have at least an 800 MHz processor, 512 megabytes (MB) of system memory (RAM), and a graphics card with 128 MB of RAM. It’s important to note that these specifications are indeed for a minimum configuration, one which will not allow you to take advantage of all of Vista’s performance enhancements. The preferred configuration would include at least a one GHz processor and one gigabyte (GB) of

system memory. Some computer makers, though, including Dell, are wisely recommending that the amount of RAM for Vista be doubled — to two GB.

Before you can decide whether or how to upgrade your PC, you have to know what’s in it. If you’ve managed to keep the original bill of sale or hardware specification sheet for your PC, you’re in luck. You’ll know exactly what you have lurking in your computer by scanning the document.

If you have no idea of what’s in your computer, never fear. There are several web sites available that can scan your computer for free and present you with a list of its major components. The best is PC Pitstop, which has an easy-to-use Vista Readiness scanner that will compare the contents of your PC against the hardware recommended by Microsoft.

Log on to PC Pitstop’s page, and click Take The Test. You may be asked to allow PC Pitstop to install a cookie onto your PC to facilitate the test. If you’re worried about the nature of the cookie, you can find a full description of any cookie that PC Pitstop uses at the PC Pitstop Cookies page.

If your PC is falls below Vista’s hardware requirements or recommendations in one or more areas, which area should you worry about most? Your graphics card is probably the most important upgrade you can make in a computer that’s less than four years old. That’s because Vista’s Aero interface draws heavily upon the graphics card. Not having enough graphics card memory will not allow you to experience Vista as it is intended to be used.

Second on the list of reasonable upgrades would be system memory. Vista will choke often even on 512 MB of RAM, and your work will frequently grind to a halt, as the hard drive churns constantly to compensate for insufficient RAM.

A hard drive upgrade may also be worthwhile, since older hard drives that spin slower than 7200 revolutions per minute will hamper Vista’s performance, which is heavily dependent upon the speed of hard drives.

If you find yourself wanting or needing to upgrade three or more components of your PC, consider selling or donating your machine and buying a completely new one. Add the cost of three or more components to the hassle of actually installing them or having them installed in your current machine, and you’re looking at a bad deal compared to the benefits of having an entirely new machine that’s been built from the ground up to handle today’s software.

Notebook users may want to spring for a new machine even faster than desktop users. Upgrading a notebook computer — especially the graphics card — can be difficult if not impossible.