In the world of CPUs, market segmentation leads to some strange pricing practices sometimes. Performance of a given chip does not scale linearly with price in many cases, and sometimes, you're paying more for the name than the part.

The main example of this is in Core 2 lineup, which is segmented into Core 2 Duo, Pentium Dual-Core, and Celeron parts. As most techies know, all these chips are Core 2 Duos to begin with; a Pentium or Celeron is made by diking out cores and/or cache that fail the quality control tests. The point being that these chips are Core 2 Duos, just cut down somewhat. What remains still has the same potency clock-for-clock.

The point is, there are other factors to consider besides simply what a chip is called and/or numbered. The most striking example I have seen thus far is the Pentium Dual-Core T4200, a "budget" laptop CPU that nonetheless performs about the same as the mid-high end Core 2 Duo T7500 according to Passmark. What is going on here?

Turns out it's market segmentation at work again. The T4200 is a newer "Penryn" 45nm core, while the T7500 was an older 65nm "Merom" core. Apparently there's so much of a gulf between the two (and the 45nm cores are so much cheaper to produce) that the actual performance matters less than the marketing divisions. Not that this is a bad thing for consumers; on the contrary, this should make a lot of laptop hunters on a budget feel better. The T4200 is more than worthy of the Penryn name, regardless of whether it's called Pentium or Core 2 Duo.

But the reverse is also true, where some companies (Dell, I'm looking at YOU) heavily emphasize brand name over performance. As an example, many of Dell's laptops let you choose between T4200, T6400, and T8100 processors, among others. There is usually a gap of $100 or more between the T6400 and the T8100, but the two chips perform almost exactly the same.

Of course no one would know that unless they did the research, and most people would get suckered in by the "bigger number = better chip" fallacy. Yes, the T8100 has an extra MB of L2 cache, but unless you're doing heavy photo or video editing there's no need for it...and a single MB of L2 does not justify that much of a price gap.

So do your research, and remember: the company is not your friend. You are not a customer. You are a consumer, a "revenue unit." And you are not the target market for CPU makers; the major OEMs and vendors are. Know your needs, know your chips, buy wisely.

You know, planned obsolescence is a funny thing. If you have a sharp eye you can get some amazing values by buying a generation or two behind the bleeding edge. I found something interesting on Newegg: AMD Phenom 9150e and 9350e processors going for $80 and $100 respectively.

Now, while the first-generation Phenoms garnered a well-deserved reputation for being slow, underpowered, hot, and (before B3 stepping) buggy, these two chips are worth a closer look. They're native quad-core parts, and they only have 65W TDPs. Each individual core is slow, but they're excellent multitasking CPUs and good for multi-threaded loads.

Now here's the interesting bit: according to Passmark's CPU list, the 9150e performs about as well as a Core 2 Duo E8400. Nevermind that it needs double the number of cores to do so: you are looking at something that has the performance of a $160+ chip for $80 in the same power envelope. Same performance, half price.

Among other things, this means an AM2+-based "budget" build could have a true quad core CPU in it, if you wanted. This is just one of the weird mechanics of the CPU market, but if I were you I'd take advantage of it while the chips are still there.

With all the excitement over Intel's upcoming Core i5 line, now would seem to be a strange time to think about building a computer. And if your budget is around the $1000 mark, it is; wait a few months for the latest and greatest from Intel and get your money's worth then.

But if you're on a tight budget, and I'm talking less than $300 here, read on: now is the perfect time to build yourself a zippy little computer, and longtime underdog AMD is the company to help you do it.

Intel has been neglecting its low end somewhat, and with all the hype over Westmere, Lynnfield, and Nehalem, less attention than usual has been paid to the sub-$100 CPU segment. This is not to say that the offerings at that price point are bad, far from it. But those chips are only good because they are, let's face it, die-harvested Core 2 Duos. The low end is in serious need of fresh air.

Enter AMD's Athlon II X2 series, codenamed "Regor." This core is an interesting beast: it's not a reclaimed Phenom II, but an entirely separate die design with 1 MB L2 cache per core but no L3. It comes in 2.8, 2.9, and 3.0 GHz speeds (240, 245, and 250 respectively). And it's aimed directly at Intel's Pentium Dual-Core line, undercutting it by $5-10 in most cases and delivering far better performance almost across the board.

Put another way: how would you like the equivalent of a Core 2 Duo E7300 for $80? Yeah, I thought so.

That's no exaggeration: benchmarks show the 250 falling somewhere between the Pentium Dual Core E6300 and Core 2 Duo E7300 for most tasks, except in a few multimedia and gaming benches where it actually exceeds the E7300. Not bad for an $80 chip, and its siblings are even cheaper.

Of course, a budget build relies on more than just a cheap CPU. Ideally, you want as much as you can integrated into the motherboard, and this is where Intel really falls down. While the CPU performance is fairly close dollar for dollar, the difference between, say, a $50 G33 Intel motherboard and a $50 780G AMD board is like night and day.

Why? Basically, graphics. Gigabit LAN, Serial ATA 3Gb/s, and 2-4 RAM slots are more or less standard now, but the X3100 and 4500HD IGPs found on budget Intel boards can't hold a candle to the Radeon HD 3xxx and 4xxx series commonly found on AMD boards in the same price range. Yes, Intel IGPs are enough to play HD content, but why not get something stronger for the same money?

Bear in mind Intel is phasing out Socket 775, while Socket AM3 (and AM2+!) will probably be around a good long while and provides an upgrade path. The compatibility is also useful, letting you reuse your DDR2 RAM and plug newer CPUs into older motherboards. At this point, at the low end there is no reason to go Intel unless you have a spare video card sitting around or the machine really is only going to be used for IM and Youtube, and if that's the case, save even more money and get a Celeron 430 and be done with it.

Welcome to Linux on Less! This is a blog about low-power and budget computing, reviews of the latest CPUs and other hot hardware, and how to get the best out of your computers old and new using GNU/Linux.