By Gareth Ogden posted Aug 31st 2010
This application note will explore the benefits of using 8GB of Corsair DDR3 system memory in a dual-channel DDR3-based PC, such as an Intel® Core™ i5 or Core™ i7 (Lynnfield) system, or an AMD AM3 Phenom II™ PC. It will show how the additional RAM allows for a 'snappier' and more responsive PC, with performance improvements of up to 186% versus a PC with 4GB of RAM. And it will also show how adding more RAM allows you to change the way in which you use your PC, by allowing you to 'do more'. This includes running more applications (and never needing to close them), working with more data, and even running another 'virtualized' operating system. For example, you could run a virtual Ubuntu Linux operating system as a pure email / home admin PC, leaving your Windows installation free for office duties, or just as a pure gaming system.
These benefits will be discussed in more detail during the course of this application note, but a summary of the performance results and benefits is shown below.
Performance Results Summary
Summary of benefits to using 8GB or more
Changing the game with 8GB
|Windows 'caches' more data into RAM||Applications are more responsive and Windows feels generally faster and 'snappier' with no delay switching between applications|
|Less / no reliance on the pagefile on the hard disk drive||The storage drive is the slowest component in your PC. Even an SSD is at least an order of magnitude slower than RAM!|
|Leave your applications running all the time||Everything is immediately available when you need it|
|Work with more and larger photo an video files||Edit longer HD video clips and work with more high-resolution digital photos, without the PC slowing down to a crawl|
|'Sleep' and 'Resume' faster||Don't shut down your PC, just save the session into memory so that you can resume from where you left off. 8GB makes this process faster|
|Have your favorite game running in a Window||Need a break? Just mouse over to WoW or Guild Wars for 15 minutes, or have a few rounds of Counter-Strike|
|Virtualize another operating system without needing to close any other applications||Use Ubuntu Linux for all your home email / finance / administration, and have a pure Windows OS gaming or office system. Or just try out different operating systems for fun!|
|Make better use of multiple monitors||With so many applications able to run at once, it makes sense to spread them out across multiple monitors.|
Over the last 12-18 months, assisted by the wider adoption of 64-bit operating systems and the increasing memory usage of applications and games, enthusiasts and gamers have accepted 4GB or 6GB of memory as the 'base level' for a modern PC.
DDR3 has also taken over from DDR2 as the memory of choice now that Intel has moved completely to DDR3 on its Core i5 and Core i7 (Lynnfield) CPUs with dual-channel DDR3 memory controllers, and AMD has made the transition to DDR3 with Socket AM3 Phenom II processors.
The increased number of platforms that support DDR3 has also helped to drive down the cost of DDR3 memory, and as a result consumers have the option to install even higher quantities of memory. Installing 8GB or 12GB of DDR3 memory would have been a luxury 18 months ago, but these larger memory densities, and potentially even higher densities, are now affordable.
8GB versus 4GB - Real World Performance Testing
To investigate the benefits of using 8GB of memory as opposed to 4GB, we built a test PC based around an AMD Phenom II 710 Socket AM3 processor and AMD790FX motherboard, which supports dual-channel DDR3 memory. Although we used an AMD platform, these benefits apply equally to any dual-channel DDR3 platform, such as Intel Core 2, Core i5 and dual-channel Core i7 (Lynnfield) processors.
We then recreated a typical desktop home/office environment, using a selection of popular office and multimedia applications. This 'Typical Application Set' was workable when using 4GB of RAM, so the aim of the benchmarks is examine whether extra memory headroom can provide performance benefits even in situations where more than 4GB is not a requirement. By recreating a typical desktop environment we can show how an application would perform in the real world. To maintain a consistent test environment, the system was rebooted and the application set reloaded after each test.
The benchmark results show that installing extra memory can provide significant performance benefits, even in situations where the overall memory usage does not exceed 4GB. Installing more memory allows the operating system to store more data in RAM, rather than relying on the pagefile on the storage drive. This makes applications respond more quickly, and provides access to your data, photos and video files without delay. Many of the benefits cannot be shown in benchmarks, and are simply the result of greater 'responsiveness' when switching between applications and performing tasks.
- Socket AM3 AMD Phenom II 710 processor
- Gigabyte GA-MA790FXT-UD5P motherboard
- 8GB Corsair Dominator GT (2 x CMG4GX3M2A1600C6)
- Corsair P256 solid-state drive
- Corsair HX1000W PSU
- Corsair H50 CPU Cooler
- Corsair Obsidian 800D chassis
- MSI GeForce 280 GTX graphics
- Windows 7 Ultimate 64-bit
Typical Application Set
Office Applications (14.3MB of data in total)
- 11 x Excel spreadshets
- 3 x PowerPoint presentations
- 2 x Word documents
- 1 x PDF document
Home Photo Editing
- Adobe Premiere Elements 7 – 25 min HD video project
Home Video Editing
- Adobe Photoshop Elements 7 – 127 photos (516MB)
- 13 x FireFox 3.5 browser tabs
- Windows Live Messenger
6 x Desktop Gadgets
Adobe Photoshop Elements 7 photo loading benchmark
In this test we timed how long the system took to load 127 digital photos, totaling 516MB, into Adobe Photoshop Elements 7. The test was run with the Typical Application Set loaded, excluding the digital photo data.
With 4GB of memory installed, the Physical Memory usage of the PC before the photos were loaded was 2.5-2.6GB, rising to 3.9GB during the test (97% total usage) and settling to 3.0 - 3.2GB after the test completed. With 8GB of memory installed, the Physical Memory usage of the PC before the photos were loaded was 2.7-3.0GB, rising to 4.6GB during the test, and settling to 4.2GB after the test completed.
With 4GB of system memory installed, the PC took 228.9 seconds to load the photos, compared to 213.35 seconds with 8GB of system memory installed, an improvement of nearly 16 seconds. The performance improvement can be attributed to the greater amount of free memory with 8GB installed.
However, the improvement in loading time was only part of the benefit. With 4GB installed, there was typically less than 1GB of free memory remaining after the photos had been loaded, compared to nearly 4GB free memory with 8GB of RAM. This extra headroom provided the 8GB PC with greater responsiveness, and the ability to switch between and use other applications without delay.
Crysis Warhead level loading
In the Crysis Warhead level loading test we timed how long it took for the 'Call Me Ishmael' level to load, as recorded by the game's console.
The results show that the level loaded over 10 seconds faster with 8GB installed, compared to with 4GB of RAM installed.
More significantly, the 8GB PC was able to load the Crysis Warhead application far more quickly than the 4GB system, which often needed to 'swap out' a significant amount of data into the page file in order to free up space. We were unable to reliably benchmark this delay, but depending on the memory usage of the system, it could take 2 to 3 minutes to display the Crysis Warhead 'splash screen' after launching the application. By contrast, the 8GB system was able to launch the game within a minute.
Time taken to 'Sleep'
Rather than shutting down a PC after use, it is more convenient to enable the 'Sleep' function, which stores the current session in memory. This allows you to quickly resume using your PC at a later time from the point at which you left off. The advantage compared to shutting down the PC is that you are able to resume using your PC more quickly, and without the need to re-load all your common applications and data.
Since the Sleep function uses memory to store the current desktop session, having more free memory makes this function complete faster, particularly when the session involves plenty of open applications and a lot of data. With 4GB of RAM installed the test PC with the 'Typical Application Set' loaded took over 116 seconds to 'Sleep', compared to 79 seconds with 8GB installed. This is an improvement of nearly 47% in favor of the 8GB system.
Time taken to 'Resume'
Perhaps more important than the time taken to 'Sleep' the PC is the time it takes to 'Resume' the stored session so that you can continue using the PC from the point at which you left off.
With 8GB of RAM installed the PC resumed the stored session in 7.7 seconds, compared to over 22 seconds with 4GB of memory installed. This is an improvement of nearly 186% in favor of the 8GB system, allowing you to resume using your PC much more quickly.
Going Beyond Performance Benefits
Don't ask "What could more RAM do for me?"…ask "What could I do with more RAM?"
Performance improvements are only part of the benefit to adding more memory, because extra RAM also allows you to use your PC in ways that you had perhaps not considered before, simply because it wasn't possible with lesser amounts of RAM. Simply put, adding more memory lets you do more with your PC.
To really appreciate the benefits of upgrading to 8GB or more of memory, you need to change your perceptions of how you can use your PC. Until recently it has been the norm for PCs to use relatively limited quantities of memory, and so we have become accustomed to working within these limits. With 8GB or more of memory, these limits can be smashed away and you can begin to realize the full potential of the latest multi-core processors and 64-bit operating systems, which are designed for multi-tasking and working with larger files.
With 8GB or more of memory you can leave your applications open all the time, so that they are available immediately when you need them. You can also use a greater number of digital files, such as HD video and high-resolution digital photos, without having to close other applications to make room. The extra memory headroom also allows you to leave your favorite game running in a window so that you can dip in an out when you like, or play a quick 15 minutes of WoW or Counter-Strike if you need a break. You can even Virtualize another operating system (or several), either to use as a pure home office / admin system, or just for fun to try other platforms. Also, with the ability to have more applications on go at once, you can make effective use of multiple monitors by spreading you applications across a larger desktop area.
These are things that you may have not thought of doing before, because with limited quantities of memory it wasn't possible. By adding more memory, you can change the way you use your PC and get more out of it at the same time.
The Corsair 8GB PC
In the performance comparisons shown above, the Physical Memory usage of the PC with 8GB of RAM installed reached around 4.6GB maximum, which means that the system still has plenty of memory to play with. As shown in our results, this extra memory headroom does provide performance benefits, but what else can you do with this extra memory?
One answer to this question is to simply 'do more' with your PC. As an example, we took the test PC with 8GB of RAM and created a desktop environment that made full use of the memory. To show just how powerful and flexible a modern, multi-core PC with a 64-bit operating system and 8GB of RAM can be, we added a second graphics card and set up a triple-monitor array, using three 22in TFTs.
The system was configured as a home/office PC that is used both for office duties, gaming and entertainment, and also for personal email, admin and finance. These three 'duties' are split across the three different monitors. However, rather than simply using a different User Account, or email account/application and folders for the personal/home email and admin duties, we have decided to use a separate operating system, running as a virtual machine. A virtual machine is essentially an operating system running within another operating system, and it behaves in exactly the same way as a normal operating system. It is essentially a second computer system running on the same CPU. Your CPU needs to support virtualization in order for this to be possible, but modern AMD Phenom II, and Intel Core 2, Core i5 and Core i7 CPUs all support this feature. We used the application VirtualBox to run a virtualized installation of Ubuntu Linux 9.04 64-bit, which we used exclusively for personal email and admin, keeping this information entirely separate from the main Windows 7 PC.
This is how we set up our 8GB triple-monitor Corsair home/office PC:
Monitor 1: Office / work applications
Microsoft Outlook 2007, 11 x Excel 2007 spreadsheets, 3 x Powerpoint presentations, 2 x Word 2007 documents, 1 x PDF document, Adobe Photoshop Elements 7, Adobe Premiere Elements 7.
Monitor 2: Gaming / entertainment
Guild Wars (windowed), Counter-Strike- Source (windowed, Servers window), FireFox 3.5 web browser windows, Spotify music player, Tweetdeck twitter application, Windows Live Messenger.
Monitor 3: Virtualized Ubuntu 9.04 x64 home email / admin PC
Thunderbird email and news application, Miro web TV, FireFox web browser, Flickr Organizer, GIMP image editor, personal finance apps and much more. Whatever you need for your home / personal admin!
Memory Usage of 8GB triple-monitor Corsair home/office PC
As you can see from the screenshots above, there's a lot going on with our 8GB, triple-screen PC. The Physical Memory usage for this system peaks at around 7GB, leaving only 1GB to spare. Perhaps a Bloomfield Core i7 PC with 12GB of triple-channel memory would be a worthwhile upgrade!
Installing 8GB of system memory in a dual-channel PC platform, such as an AMD Phenom II or Intel Core 2, Core i5 or Core i7 (Lynnfield) PC, leads to increased performance as a result of greater memory headroom. Using 8GB of memory also allows you to work with a greater number of applications and a higher quantity of data, without the system slowing down, or you needing to close applications to free up memory. The 8GB PC is generally more responsive and 'snappier' in use.
Additionally, the extra memory headroom allows you to use your PC in ways that are not possible with smaller quantities of memory. By making effective use of multiple monitors, a PC with 8GB or more of system memory can take full advantage of the latest multi-core CPUs with virtualization technology, and the latest 64-bit operating systems, which are designed with multi-tasking in mind.
Overall, installing 8GB of memory improves performance and productivity, and it allows you to simply 'do more' with your PC.
© August 2009, Corsair Memory, Inc. All rights reserved. All trademarks and registered trademarks are the property of their respective owners in the United States and/or other countries.