Log in

View Full Version : To Quad or Not to Quad, That is The Question


Jason Dunn
06-10-2008, 03:00 PM
<img vspace="6" hspace="6" border="0" align="left" src="http://images.thoughtsmedia.com/resizer/thumbs/size/600/zt/auto/1213029472.usr1.jpg" alt="" />When both Intel and AMD began the move to multiple cores a couple of years ago, it began a shift in the industry away from focusing on maximum megahertz and toward the idea spreading out the work over multiple processing cores. While Intel and AMD have poured significant resources into coming up with better and better multi-core designs, for the most part the the software industry hasn't been able to keep up. <br /><br />Time after time, I'll see a program stuck at using one core, which is frustrating because I know if that program was using the second core it would complete its task much faster. When I built my <a href="http://www.digitalhomethoughts.com/news/show/31593/building-a-monster-media-machine-using-shuttle-s-sd39p2-xpc.html" target="_blank">monster media machine</a> last year, I used the most powerful CPU Intel had at the time: the <a href="http://www.digitalhomethoughts.com/news/show/31593/3/1/8" target="_blank">Intel Core 2 Extreme X6800</a>. This dual-core beast of a CPU runs at 2.93 Ghz and has 4 MB of L2 cache. It chewed through everything I threw at it. Technology never stops marching, however, so only a few months after publishing that article, Intel's quad-core CPUs were taking centre stage. <br /><br />A few months ago I thought it would be interesting to answer the question many geeks are probably asking themselves: is it worth it to move from a dual-core CPU to a quad-core CPU? Many of the motherboards from 2007 are compatible with the Intel quad-core CPUs, but when does it make sense to replace your Intel dual-core CPU with a quad-core CPU? This article aims to answer that question. I requested an <a href="http://processorfinder.intel.com/details.aspx?sSpec=SLACQ" target="_blank">Intel Core 2 Quad QX6700</a> from Intel Canada to compare an Extreme CPU to an Extreme CPU, but they didn't have one for me to test, so I was sent an <a href="http://processorfinder.intel.com/details.aspx?sSpec=SLACR" target="_blank">Intel Core 2 Quad Q6600</a> instead. The Q6600 is just over 500 mhz slower than the X6800 I was using, but it has two more cores and double the L2 cache. How would it measure up? Let's dig in. <MORE /> <strong><font size="4"><br /><br />Benchmark, Benchmark, Then Benchmark Some More</font></strong><br />There's only one way to approach an article like this: lots of testing. So, in that light, I started with one of the most CPU-intensive tasks you can ask of a system: transcoding a DVD. With the Intel Core 2 Extreme X6800 CPU installed, I took one of my two copies of Lord of the Rings (I keep one just for testing) and ripped chapter eight to a 720 x 480 Divx, 2025 kbps file (set to 2 pass encoding, deinterlacing) using <a href="http://www.slysoft.com/en/anydvd.html?aid=50312" target="_blank">CloneDVD Mobile</a> [affiliate]. It took <strong>1 minute and 39 seconds</strong> to finish. At peak CPU usage, it was using 68% of the CPU. Next I tried the same encoding task, this time selecting an iPod Touch preset, which is a 480 x 270 h.264 759 kbps file. Two pass encoding was selected, and it took <strong>2 minutes 22 seconds</strong> to complete the task - with the CPU peaking at 98% usage. <br /><br />Next I performed a test using <a href="http://www.photodex.com/products/proshowgold/" target="_blank">ProShow Gold 3.2</a>. ProShow is a photo slideshow application that creates extremely high-quality video output, and it's also well-known for its ability to scale to multiple cores. I took a batch of 30 photos and output them to a 1080p video file (1920 x 1200 resolution) with high-quality encoding. The processing took <strong>9 minutes 58 seconds</strong>, and ProShow reported it was running at 0.3x realtime speed. <img vspace="5" hspace="5" border="1" align="left" src="http://images.thoughtsmedia.com/resizer/thumbs/size/600/dht/auto/1213039418.usr1.jpg" alt="" /><br /><br />Swapping the quad-core CPU into place was a quick affair, and once I got it installed I repeated the same benchmarks as above. The DVD ripping test took the same length of time: <strong>1 minute 39 seconds</strong>. The CPU usage peaked at 45%, meaning that most of two cores were being used, but the other two cores were completely un-touched. The added cache of the quad-core CPU had no impact on the speed of the transcoding. <br /><br />The h.264 DVD test showed improvement with four cores: the transcode was finished in <strong>1 minute 42 seconds</strong>, which is an <strong>18% improvement</strong> in speed. The encoding peaked at 85% overall CPU usage, meaning CloneDVD Mobile when encoding to h.264 is able to utilize all four cores, something it's unable to do when encoding to Divx.<br /><br />Next I tried the ProShow Gold 3.2 test, and this test really showed the power of four cores: the 1080p encoding process was finished in <strong>6 minutes 13 seconds</strong> (0.48x realtime) which is an impressive <strong>38% faster</strong>. My tests were purposefully small, but you can easily see the significant time savings can be had when working with larger projects (ripping the entire DVD, encoding 300 photos to 1080p, etc.). The big caveat is that the software application has to support multiple cores - and as we saw with the CloneDVD Mobile test, it sometimes comes down to the video codec itself.<br /><br /><PAGE /><br /><font size="4"><strong>What About Other Applications?</strong></font><br />After running my comparative video rendering tests, I decided to expand my testing and began seeing which applications would really take advantage of those extra cores. <a href="http://www.corel.com/servlet/Satellite/CorelCorp/en/Product/1185293056448#versionTabview=tab0&amp;tabview=tab0" target="_blank">Corel DVD Copy 6</a> was certified for dual-core use, so I tested it to see if it worked with four cores. The results were mixed. Encoding to the Zune profile (1 mbps h.264), overall CPU usage was only about 35%, meaning it was using less than two cores. This maps to what I saw when I was using it with the Core 2 Duo Extreme CPU &ndash; it would only use around 65% of the total CPU power. I tried a different profile, this time doing an HD up-convert to 720p WMV (1280 x 720) at 8.6 Mbps. CPU usage was better this time, peaking at 85% - so all four cores were being used. This is because it's using Microsoft's own Windows Media Encoder behind the scenes and it scales very well with multiple CPUs.<br /><br />I contacted Corel and they explained that while DVD Copy 6 was certified and optimized to work with dual-core systems, it wasn't certified or optimized for quad-core systems. So, basically any use of all four cores (like I saw with the WMV encoding) is a happy coincidence. I hope to see Corel update DVD Copy 6 to be fully compatible with quad-core systems, because there's certainly no shortage of them coming onto the market: my local Best Buy has quad-core Intel systems for under $700. So the hardware is there, but the software isn't quite ready for it. I also edited some raw images with <a href="http://www.adobe.com/products/photoshoplightroom/" target="_blank">Adobe Lightroom 1.4.1</a>, curious to see if it would be able to utilize all four cores &ndash; it wasn't, at least not consistently. If I rapidly moved between the raw images I'd see the CPU usage spike to 58%, but when the raw preview was being generated for an image it only used 28 to 48% of the total CPU power. Considering how much work I do in Lightroom, having full quad-core support would benefit me greatly. I'm hoping that Lightroom 2.0 (<a href="http://labs.adobe.com/technologies/lightroom/" target="_blank">now in beta</a>) will address this issue.<br /><br /><a href="http://www.adobe.com/products/premiereel/" target="_blank">Adobe Premiere Elements 4.0</a> is a video editing application I use quite a bit (though I'm hoping to change that soon), and the results of my tests were similar to what I saw from the other applications. Encoding to WMV used around 80% of the total processor power, so all four cores were being used, though not fully. h.264 encoding was less effective, using up about 35% of the total CPU power. So no love here.<br />One of my favourite applications lately is <a href="http://www.techsmith.com/camtasia.asp" target="_blank">Camtasia 5</a>, a superb tool for creating screen recordings <a href="http://www.youtube.com/watch?v=-ApVzxiZYtI" target="_blank">like this one</a>. Crunching a 10 minute screen recording to h.264 is a lengthy process, so I was eager to see if Camtasia could scale to the Intel quad-core CPU. Sadly, it doesn't even use two cores &ndash; when I was rendering a project to h.264 is only used 25% of the total CPU power, meaning one core. That's really disappointing, because sometimes I'm doing a screen recording of something that's brand new and getting my recording up onto YouTube as fast as possible is critical. I really hope <a href="http://www.techsmith.com" target="_blank">Techsmith</a> (the makers of Camtasia) are working to add multi-core support to Camtasia - it's a waste of my time to have an application only use one-quarter of the CPU.<br /><br /><font size="4"><strong>Going Green: Power Usage With the Intel Q6600</strong></font><br />I have a Belkin UPS that has a neat feature: it shows me the exact power draw placed upon it. I decided to see how smart the Intel Q6600 was when it came to power, and was extremely impressed with what I discovered. Check this out:<br /><ul> <li>With all four cores firing at 100% load, power load was 235 watts </li> <li>With three cores at 100%, one idle, power load dropped to 228 watts </li> <li>With two cores at 100%, and two idle, power load bounced between 210 watts and 220 watts </li> <li>With one core at 100%, and three idle, power load was 196 watts </li> <li>With all four cores idle, power load was 159 watts </li></ul>That test tells us that the Intel Q6600 is able to supply power to each core independently, meaning that you're not wasting power by having a four-core CPU if you're not using all the cores. That's a great feature and something that will become even more important as we move forward into eight-core CPUs.<br /><br /><font size="4"><strong>Pushing the Envelope: Overclocking the Intel Q6600</strong></font><br />I couldn't write about a CPU without also writing about my attempts to push it past the stock speeds. I am by no means an expert overclocker, having never installed a water-cooling system (or the more exotic options), but I do try to squeeze a little extra speed out of every CPU that I have. When I started researching overclocking on the Q6600, I discovered that it's quite the darling of the overclocking world. It runs stock at 2.4 Ghz, but there are numerous Web sites with how-to articles pushing the CPU up to nearly 3.4 Ghz, a massive 1000 Mhz improvement in speed. There's a catch though: only certain versions of the Q6600 (called &quot;stepping revisions&quot;) are capable of those speeds. The Q6600 I was sent was the original revision and not well known for its overclocking abilities. I figured I'd give it a try anyway!<br /><br />I started out with the CPU and RAM at stock speeds and stock voltages, and was able to push the system bus speed from 266 mhz (2.394 Ghz) up to 300 mhz (2.7 Ghz) without requiring any extra voltage. It ran stable at 2.7 Ghz, but to get it up to 310 mhz bus speed (2.79 Ghz) I had to lock the <a href="http://www.kingston.com/hyperx/default.asp" target="_blank">Kingston HyperX RAM</a> in at 2.2 volts. Windows Vista would boot when the bus speed was set at 320 mhz, giving me an overall speed of 2.88 Gz, but when I ran <a href="http://www.passmark.com/products/bit.htm" target="_blank">Passmark's BurnIn Test</a>, it would bluescreen. Keeping it locked at 320 mhz, I began inching up the CPU voltage +25 mv at a time (the RAM was still set at 2.2 volts). I got up to +200 mv over standard, which was 1.48 volts (the CPU can handle up to 1.5 volts), and the system still wasn't stable so I backed off completely on the voltage. Scaling back 1 mhz bus speed at a time, I ended up with a stable bus speed of 318 mhz, with an overall CPU speed of 2862 Mhz. At that speed, I was running 462 Mhz above stock, and within spitting distance of the Intel X6800 running at 2.93 Ghz. It passed all manner of torture tests at 2.86 Ghz, but a few days after setting that speed I was editing some photos in Lightroom while simultaneously ripping a DVD and my system crashed. I scaled it back to 315 mhz bus speed, 2835 Mhz, and it's been stable ever since.<br /><br /><font size="4"><strong> </strong></font> <font size="4"><strong>Quad-Core: It's What's For Dinner</strong></font><br />Despite my mixed results with the various software applications I tested, I'm extremely impressed with the results of moving from my Intel Core 2 Duo Extreme CPU to the the Core 2 Quad CPU - especially when you consider the fact that the original price of the Core 2 Extreme process was north of $1200 USD while the Q6600 can be had for just over $200 USD. Even if you give up 500 mhz in speed, that's $1000 that can be used for other components - or a second computer. Once you factor in the overclocking, if you're comfortable with doing that, the Q6600 looks even better - overclocking closes the speed gap and still gives you the extra cores for processing. So if you don't want to upgrade your motherboard and move to one of the new 45nm processors, the Q6600 is a great product worth considering over whatever dual-core CPU you have now.<br /><br />I hope that 2008 is the year when we see application after application add support for four or more processors - multi-core processing is definitely the future, and it's frustrating to be held back by developers who are unwilling or unable to bring their applications up to date. In the meantime, I love watching Intel continue to crank out better and better CPUs. It's a great time to be a geek!<br /><br /><em>Jason Dunn owns and operates <a href="http://www.thoughtsmedia.com" target="_blank">Thoughts Media Inc.</a>, a company dedicated to creating the best in online communities. He enjoys <a href="http://photos.jasondunn.com" target="_blank">photography</a>, mobile devices, <a href="http://www.jasondunn.com" target="_blank">blogging</a>, digital media content creation/editing, and pretty much all technology. He lives in Calgary, Alberta, Canada with his lovely wife, and his sometimes obedient dog. He dreams of someday processing HD video at 10x real-time speeds.</em>

Jason Dunn
06-10-2008, 06:06 PM
For a great look at what's coming next with Intel CPUs, this is a great article:

http://www.anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3326&p=1

Faenad
01-20-2009, 06:03 PM
especially when you consider the fact that the original price of the Core 2 Extreme process was north of $1200 USD while the Q6600 can be had for just over $200 USD. Even if you give up 500 mhz in speed, that's $1000 that can be used for other components - or a second computer. But why would you be comparing the price you paid for the Core 2 in 2007 with the price you paid for the Q6600 in 2009?
It's puzzle me, especially for computer equipment where prices drops all the time
You also compare the Q6600 overclocked with the Core 2 Extreme at stock speed.


If you compare the Q6600 with a similarly priced Core 2 Duo like the E8400 (in fact the E8400 is about 30$ cheaper) you will see that the two cores of the E8400 are more efficient in the majority of the applications.

The E8400 beat the Q6600 in all the applications that are not quad core optimized, and its 25% faster frequency also give him the edge in many apps that use four core but where the two extra cores only grants a slight speed increase.

It's also less power hungry and taking overclocking into account will not change anything as the E8400 is as good an overclocker as the Q6600.

It would only make sense upgrading today from a Core 2 Duo to a similarly priced Quad core if you do a lot of video editing.
And there would certainly be better use of the 200$ -If you works on big video files, upgrading from a single HDD to two HDD in Raid for example-

Jason Dunn
01-20-2009, 07:07 PM
But why would you be comparing the price you paid for the Core 2 in 2007 with the price you paid for the Q6600 in 2009?

You must have missed the date on this article: I wrote on June 10th, 2008 - so that's seven months ago. :)

If you compare the Q6600 with a similarly priced Core 2 Duo like the E8400 (in fact the E8400 is about 30$ cheaper) you will see that the two cores of the E8400 are more efficient in the majority of the applications.

Unless I'm mistaken, the E8400 wasn't available seven months ago when I wrote this article, so it's kind of hard to make comparisons today. I understand your point though about the validity of sticking with faster dual-core processors vs. slower quad-core processors. It really depends on the type of application that the person is using. When I'm rendering video with Adobe Premiere Elements and I see it using 90% of my four cores, that's going to render faster than a two-core CPU, even if those two cores are 400mhz faster than my quad-core.