If Christmas were six weeks later this year, my annual how-to-buy-a-computer column would be a lot easier to write.
That's because every PC on the shelves right now uses a version of Microsoft Windows that will be gone by Jan. 30, when Microsoft releases Vista - the latest update to its flagship operating system.
Normally, I'd advise readers to wait till the new version of Windows comes out. But 'tis the season, and some shoppers need a PC right now. Still others think this is a great time to pick up a bargain computer as retailers sell off their inventory of perfectly good machines running Windows XP or Media Center Edition - both of which are debugged and reliable.
And prices are down. During the week after Thanksgiving, the average laptop sold for $708, down 17.3 percent from last year, according to Current Analysis Inc. The average desktop sold for $464, down 5.9 percent.
With those figures in mind, here's my annual, component-by-component guide to buying a PC.
Vista compatibility: Many manufacturers are offering free or low-cost Vista upgrades to holiday season buyers. If you think there's a chance of upgrading to Windows Vista, make sure the PC is labeled as Vista-ready. And make sure it's ready for the version of Vista (basic or premium) that you expect to buy.
Processor: Also known as the central processing unit, or CPU, this is the heart of any PC - the chip that does the real computing. Intel is the biggest supplier, but many consumer PCs use chips from Advanced Micro Devices (AMD). They'll all run the same software. Within a brand, the main differences involve the model designator and speed, measured in billions of cycles per second, or gigahertz (GHz). Faster is better.
You find more than normal variation this year as Intel shifts to a new line of chips called Core 2 Duo and manufacturers dump older models. Dual core machines split processing chores between two processor cores - a tactic that accelerates multitasking.
Older Intel desktop models may still use the Pentium 4, while laptops use the Pentium M, or first-generation Core Duo chips. Low- end machines will have Intel Celeron chips - a bargain-basement version of the P4.
At the top of the line for AMD are the company's Turion and Athlon 64 X2 processors, which also have dual cores. For the time being, Intel's fastest are a little faster than AMD's fastest, which matters if you're calculating hyperspace travel routes or playing high-end shoot'em-ups.
For high-end gaming, video editing and Vista Premium upgrade capability, stick with an Intel Core 2 Duo or high-end AMD chip. For basic computing under Windows XP, virtually any processor will do.
Internal memory: Also known as Random Access Memory, or RAM, these chips store programs and data when the PC is running. The more RAM, the faster and more reliably your PC will run. In fact, adding memory is often better than buying a slightly faster processor. The store can install additional memory before you leave - often for the cost of the chips alone.
Memory is measured in megabytes (millions of bytes or MB) and gigabytes (GB). For Windows XP, 512 megabytes of memory will usually suffice, although a gigabyte is better. For Vista, Microsoft has upped the ante to at least a gigabyte, and the wise guys I know are urging 2 GB for Vista Premium. This will bump up PC prices.
Hard drive storage: Your hard drive stores programs and data permanently and shuttles information back and forth from your computer's memory when it is needed. Capacity is measured in gigabytes, or billions of bytes.
Hard disks are so cheap that it hardly pays to economize here. In fact, few consumer desktop machines come with less than 80 GB, with most in the 160 to 200 GB range. Laptop makers are a bit stingier, typically providing 60 to 100 GB.
The only reason you'll ever need more than 150 GB is if you want to store lots of video. In that case, buy a computer with a drive in the 200 to 400 GB range. If you want still more space, external hard drives that attach to a USB port start at $150 for 300 gigs. They're good buys.
Video: This is where future Vista capability may require a decision now. The video adapter determines what you see on the screen. For basic, pre-Vista computing - which means anything less arduous than high-end gaming - the Intel-based video adapters in most entry and mid- level PCs are just fine.
However, to enjoy gaming or savor the fancy graphics of Vista Premium, you'll need a dedicated graphics adapter with its own video memory. Most of these have graphic chip sets from nVidia or ATI, and that will be noted on the sticker.
Vista premium requires at least 128 MB of video memory, but gamers will need even more power and twice that much video RAM. If the desktop machine you like doesn't have enough video horsepower, you can buy a plug-in video card after the fact. But with laptops, shop carefully now - you're pretty much stuck with what you get.
Optical disk: With the exception of lightweight laptops, all PCs have some form of CD or DVD drive. If nothing else, you'll need one to load commercially sold programs and back up your data. If you can, get a machine with a DVD-RW drive, which can play and record DVD movies as well as music and data. If you don't care about making DVDs, look for a computer that plays DVD movies but only records on standard CDs.
Monitor/laptop screen: For desktops, a 17-inch, flat-panel liquid crystal display (LCD) will do fine, although aging eyes will appreciate a 19-inch model.
If you're looking at laptops, choose a 14-inch or smaller screen only if weight and portability are paramount. A 15-inch screen is much more comfortable. Widescreen laptops are good for movies but I don't think they're worth the additional bulk.
Be wary of high-gloss, super-high contrast screens. They display movies well but produce too much glare for workday applications.
Audio: The PC is now the entertainment center of choice for many young people, so most have acceptable audio playback circuitry built in.
Musicians and gamers who want better control of 3D sound and superior recording power should look for a high-end sound card from Creative Labs or Voyetra Turtle Beach. You won't find these on most off-the-shelf, entry-level machines, but most PCs can easily be upgraded with a new sound card.
Whatever the computer's capabilities, the speakers bundled with most PCs are awful. A decent set of speakers will turn the system into a joy for music lovers - money well spent.
Good three-piece systems (two desktop satellite speakers and a bass subwoofer) will satisfy most musical tastes for $100 to $150. Hard-core gamers and movie buffs may want five- or seven-piece systems that envelop you in sound. Performance varies widely - listen in at the store.
TV: Television tuners are popular accessories, particularly on computers running Windows Media Center Edition. MCE players already have software that will turn a tuner-equipped computer into a Digital Video Recorder, just like a TiVo.
Tuner-equipped PCs running regular Windows XP usually have a third-party DVR program on-board. Vista Premium will have DVR capability built in, too.
Caveats: High-definition recording capability is likely to be nonexistent or downright iffy, so don't expect miracles from tuners in this generation of PCs.