Should You Buy A Dual Core Processor?

And Who Should Stick To A Single Core For Now...

Recently, I was posed the question of "Should I buy a dual core processor?" from an acquaintance. That got me thinking as to whether the dual core chips have reached the level of the average consumer, and I'd like to share some thoughts.

I had a friend, a few years back, that ran two 300A Celerons overclocked to 500 MHz for his desktop. He used to boast that he had "One Gigahertz" of power, when there were no 1 gig chips on the market. Well, not quite, but he was ahead of his time, and onto something in a high performance way. Even when faster processors were introduced, he was still quite happy with his dual processor setup, at least for longer than most.

The dual core chips have been out for just over a year for desktops. Both Intel and rival AMD offer dual core products. For desktops, Intel offers their Pentium D line of chips. AMD's line of dual cores are the Athlon X2 chips. Lest things get too clear, Intel will be releasing a new line of dual core desktop chips based on their highly anticipated Conroe chip. And to really keep us all confused for a while, they're calling these desktop chips the Core Duo 2 chips, even though the Core Duo (1) processors are for mobile applications. Clear as mud yet? I thought so!

AMD declared the megahertz wars over several years ago, achieving competent performance from its Athlon series of processors without needing to ratchet the clock speed up to faster-than-light proportions. In the meantime, Intel finally hit its wall of brute force performance at 4GHz, retreating backward instead of delivering on the promised CPUs and the awesome heat they’d develop. This was also hastened by the acceptance of AMD's PR ("performance rating") numbering scheme, as well as the success of Intel's Pentium M (the essential ingredient of Centrino for notebooks) which showed, even to Intel's diehard "more megahertz faithful," that great performance could be had at lower clock speeds with faster front size buses, and megagenerous amounts of processor cache (and not to forget 64 bit processing on the AMD side of things).

Even with these internal tweaks, however, chip makers were still faced with a barrier when it came to performance and megahertz. The solution, was to offer another processing core. Instead of two separate processors though, they went with the two processors housed on one chip- the so called dual core chip.

There was a profound difference between the Intel dual core and the AMD dual core. This is most notably in the Crossbar Switch which allows the dual core Athlon chips to directly communicate data between the cores. (At full processor speed, no less). The Intel chips have to route the data off the processor to send it from one core to the other, a far less elegant, and slower solution.

While the dual cores performed ably, early benchmarks did not show a doubling in performance speed on routine tasks (and in some cases little to no performance increase). However, when running multiple benchmarks simultaneously, like video editing while playing a game, is where the "dualies" started to show their performance value.

Now that we're all up to speed on the history of dual core processors, we can return to the question of "Should I buy a dual core processor?" I think, like many other things in life, the answer is it depends on what you intend to do with it. After all, there's nothing wrong with all the single core processors out there, many of which can be had for significantly less money.

If your computer uses are limited to email, word processing, viewing images, and other basic tasks, then a single core processor is right for you. Likewise, if your budget for a chip is under $100, then your choices are limited to a single core processor. Look for a Celeron, Sempron, or older Athlon 64, just don't look for a dual core chip. Your budget is too low to afford it, and your needs too basic to justify it anyway. These users should simply snap up a bargain, and be on their merry way. After all, my AMD K6-2 475 MHz processor can handle these tasks without breaking a sweat so even the slowest current Celeron or Sempron should be more adequate overkill on these tasks.

Once we get beyond the sub-$100 price point is where things get quite intriguing. The lowest priced Athlon X2 processor is the 3800+ which is currently just under $300. The comparable single core product, going along with AMD's numbering scheme, is the Athlon 64 3800+ processor, which retails for $284. The $13 price difference is quite a small price of admission into dual core territory here, and I doubt that many single core 3800+ chips are being sold these days. You can see an excellent head to head comparison between the two chips here. On many of the benchmarks, the X2 is faster than the 64, particularly on benchmarks. On a few games that take advantage of single threaded applications, the 64 is a little faster, but the X2 more than holds it own, and doesn't give up much.

The $300 price of admission to get into an AMD X2 dual core may still be a little too hefty for some. The good news is that Intel's dual core offerings start at an even lower cost. How about, as of today, less than $200! The better news is that they are expected to drop in July even further. The current dual cores from Intel less that $200 are the Pentium D 930 for $196, the 820 for $175, and the truly bargain 805 that is down to $126. As an aside, Intel really gave enthusiasts a gift with the Pentium D 805 as it is the most overclockable chip in recent times.

I really had to look around to figure out what to compare the 805 to. When Anandtech reviewed the 805, the single core Intel offerings were the Pentium 631, and the Celeron D 351. The 805 was neck and neck with the 631 on many tasks, faster on others, and slower on some game related benchmarks. A wash in my mind. The Pentium D 805 was faster than the Celeron D 351 on every benchmark. The Pentium 631 retails for more money at $176 than the 805 making it a no brainer for the dual core. The Celeron 351 sells for $74, making it a reasonable choice for the sub $100 computer. It is no real competition to the Pentium D 805 in the end.

Ok, now that we realize that the dual core chips can be had at similar price points once we are willing to pay more than $100 for a processor, we start to see that there really is no reason to buy a single core processor in this day and age.

While it is true that almost no software is optimized yet for the dual core chips, that certainly is the trend. I fear that the older single core chips just won't be able to run this multithreaded code. The dual cores run today's applications fine, and will be ready for tomorrow's- assuming it goes towards code designed to take advantage of the dual processors able to run multithread code with ease. If not, they are still more than capable on the full variety of tasks. The one possible exception is that on gaming tasks, the single core processors are a little more adept at providing frame rates- although, as we all know, this is even more dependent on the graphics card anyway.

The answer is often given that you should buy a dual core processor if you run multiple applications simultaneously, which would be given by someone who doesn't really understand the concepts here. The short answer to that is that we probably all do a certain amount of multitasking in the end. While you may not render video while you play games, take a look at your tray in the lower right hand portion of your window. Most of us have several applications all running in the background: antivirus, antispyware, instant messaging, mouse drivers, and networking are in mine. I'd bet that you have your share of baseline code running all the time as well. While chips get benchmarked with clean Windows installs, and no other applications running, our desktops at home and work simply are not set up this way. And this is where a dual core chip will really shine. With two cores to share the load, the processing can be done a lot more efficiently.

In summary then, if you are in the budget sub-$100 processor club, then you're limited to a single core chip, at least for the time being. Alternatively, if you have more than a barebones budget, and have real world computer tasks (or even more advanced) then you will be better off with a dual core chip than the comparable single core processor as we've discussed above. In other words, definitely think dual core when planning out your next system.

--Jonas