Image Quality, Conclusion
Perceived image quality is an issue that is hard to talk about with discrete GPUs, but also important. It is theoretically possible for a game to look better at lower detail settings if it’s being rendered at a higher quality. But can you really perceive a difference?
To try and find out, we’re going to look at two sets of screenshots. One is from Diablo 3, a game that has a plethora of beautiful lighting effects. The other is from Skyrim, which gives us a great chance to check out real-world texture filtering quality.
All test samples were taken at the image quality settings used to benchmark the games.
Let’s start with Diablo 3.
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This is Tristram, the first village you have as your home base, and the one with the most dynamic lighting. For the most part, each sample from each graphics solution is nearly identical. However, there is one exception: shadows. While the NVIDIA and Intel solutions rendered stark, hard-edged shadows, Trinity’s Radeon HD 7660G rendered softer, more natural shadows. It’s a pleasing effect and one that’s often noticeable in Diablo 3.
I also think that, if you squint at the images hard enough, the Intel HD 4000 sample looks a little duller than the other two. I notice this most in the grass, which is a bit less colorful. I also notice it in the design on top of the player stash. It looks flatter and less detailed on HD 4000.
Author's Note: After this article was published Blizzard has patched in an option that lets players decide if they want hard-edge or soft-edge shadows in Diablo 3. This removes the major difference in image quality between AMD, Intel and Nvidia – all three are nearly identical.
What about Skyrim? Let’s have a look.
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When I took these images on the laptops themselves I perceived them to be the same, but when I saved them and compared them side-by-side on my desktop I noticed an immediate difference in color. The NVIDIA sample is simply yellow-er (is that a word? [heh, we'll go with it]) than the other two. All of these screenshots are taken from the same save at the same time of day so, as far as I’ve been able to discover, the GT 640M is rendering light a bit differently.
After spending a fair bit of time staring at these images I feel that the Radeon HD 7660G is also a bit darker than the Intel HD 4000 sample, which is the brightest. In terms of texture quality, I have a hard time perceiving a difference. I do know that even in synthetic test images all of these solutions have similar texture filtering properties, so I’m not surprised at this result.
Overall, I think that the Radeon HD 7660G has the most attractive image quality, but I also must point out that this advantage is minimal and obscured by display quality. This was obvious when I took the screenshots, viewed them on the laptops running the games, and then transferred them to my desktop and its Dell Ultrasharp display. The difference – particularly in the colorful yet dark Diablo 3 – was night and day. If image quality is your concern you should devote all of your attention to the quality of a laptop’s display, and treat the graphics solution as a secondary concern.
I think it is obvious from these results that none of the IGPs on the market today, including Trinity, are capable of satisfying anyone who might label themselves a gamer.
Intel’s HD 4000 is adequate in the sense that it can offer a playable experience in most games at 1366×768, but you will have to turn down the detail below the modest settings we used in this round-up. Trinity is a bit more than adequate in the sense that it will let you turn up some settings in games and still have a playable experience, but just barely.
If you want a decent gaming experience you will do yourself a huge favor by considering a low-end discrete solution like the NVIDIA GT 630M. This solution offers a clear advantage over Intel HD 4000 and is also better than Trinity because, besides offering better overall GPU performance, you aren’t tied down to a lackluster CPU. Three of the five games tested (Dawn of War 2: Retribution, Civilization 5 and Diablo 3) were playable even at 1080p on the GT 630M.
The GT 640M, which already impressed me in its review, only continued to prove itself here. It was able to handle all of the games at 1080p and provided excellent framerates at 1366×768. A gamer with a laptop that maxed out at 1366×768 would be able to play most games at high detail.
AMD does offer alternatives to NVIDIA’s GT 640M such as the HD 7730M and HD 7750M, but I suggest going with NVIDIA if possible. I think the green team has a much better driver software interface. I also think that Optimus is a smoother (and more mature) switchable graphics solution. With that said, I don’t encourage readers to put a huge weight on NVIDIA’s products. If you prefer a certain laptop that is only available with Radeon graphics, buy it – but if all other things are equal I recommend going with the NVIDIA equipped laptop. [In the end though any discrete card will be better than none at all.]
I think that these findings prove there is still a lot of life left in discrete laptop GPUs. Both Intel and AMD have made huge strides with their IGPs and improved them substantially relative to previous versions, but the requirements of modern games aren’t standing still. Display resolutions seem to be on the rise, as well. There’s definite interest (for good reason) in making 1600×900 and 1080p displays common among laptops, but all the IGPs struggle to cope when asked to push more pixels.
Discrete GPUs also appear to be a good value. Though more expensive, they more than justify their price by providing substanially better performance. It's usable performance, as well. A better GPU will let you play more games and enjoy higher detail settings.
Don’t confuse “adequate” with “enjoyable” and don’t succumb to the lure of saving a couple hundred bucks. Most people keep their laptops for at least three years, so if you have an interest in gaming a mid-range discrete GPU is a wonderful value you’d be crazy to pass on.