Technology Lab / Information Technology


Piledriver comes to the desktop.


Ok, look, I have a project scope problem. Including frame-by-frame data across multiple games for 22 different processors, along with everything else, probably wasn't the wisest move. We may need to re-think our approach.

To help you deal with the data overload, we've boiled our results down to a few simple scatter plots showing price versus performance. We've averaged performance across several sets of tests using a geometric mean. The first plot is based on our overall CPU suite, including the discrete gaming tests but not IGP gaming. The second plot isolates just the discrete gaming tests, and the third one covers only the IGP gaming tests. For the gaming plots, we've converted our 99th percentile frame time values into their FPS equivalents. As ever, the best position on each plot is the top left-hand corner, where prices are low and performance is high.

If you've been following the x86 processor wars lately, you might be surprised to see that the A10-5800K beats the Core i3-3225 in overall performance, while the A8-5600K ties it. (You probably aren't surprised to see the pitiful Pentium G2120 buried at the bottom left of the scatter plot.) Trinity's strength here comes from its four integer cores (versus two for the Intel competition) and the fact that our CPU performance suite is very nicely multithreaded, as a rule. Trinity's per-thread performance is still a significant weakness, but AMD has priced the A10-5800K and A8-5600K appropriately, given their performance. Just don't forget that Trinity is matching the Core i3-3225's benchmark numbers by carving out nearly double the power envelope for itself.

Click over to the discrete gaming scatter, and you'll see something of a remix of our recent CPU gaming article. To those folks who requested the inclusion of a Core i3 the next time around: you were right. The Core i3-3225 is one heckuva budget gaming chip, faster overall than any CPU in AMD's lineup. The Trinity-based APUs aren't terrible for gaming, but their pokey per-thread performance can impact the smoothness of frame delivery. In some cases, like our single-player Battlefield 3 test, the impact may be minimal. In others, you're likely to feel it. The A10-5800K just matches the gaming performance of the Core i5-655K, a two-generations-old dual-core Intel part—and it does so in nearly twice the power envelope of the much faster Core i3-3225. If you plan to plug a discrete graphics card into your system, you'd do well to go with a recent Intel CPU instead.

Just make sure that CPU isn't the Pentium G2120, whose woeful performance in a couple tests proved to us that you probably do need 3-4 cores, or at least threads—or, you know, maybe AVX and higher self-esteem—to run today's games optimally.

Pop over to the IGP gaming scatter plot and the story's a simple one. The A10's faster graphics extend AMD's lead. Of course, to keep beating the drum, the A10 achieves its higher performance by using nearly twice the power envelope of the Core i3-3225, so its dominance should come as no surprise. Considering its power envelope handicap, Ivy's IGP isn't nearly as far behind Trinity's as one might think. I'd still trust AMD to provide better drivers for its Radeon graphics solutions than Intel does for its IGPs, but the HD 4000 did manage all of the big-budget titles we threw at it without any crashes or obvious visual artifacts. Intel is clearly paying more attention to software support than it has in the past.

The games we used are indeed AAA titles, and they required relatively low resolutions and quality levels just to achieve playable frame rates. That's what you get with IGP gaming these days. There are tons of indie and casual games whose requirements are much lower; they'll run well on just about any modern IGP. But in such cases, the performance differences between the Intel and AMD integrated graphics solutions are less likely to matter.

We still think serious gamers will want to add discrete graphics cards to their systems. Expandability is one of the hallmarks of a desktop PC, after all. Even a relatively affordable card like the Radeon HD 7750, which sells for as little as $89 at Newegg, will run today's games competently at two-megapixel resolutions and decent quality levels. We're talking about a vastly superior experience to the one these integrated graphics processors can muster. What's more, the Radeon HD 7750's TDP is just 55W. Add that to the 55W of the Core i3-3225, and you've only exceeded the A10-5800K's max power rating by 10W. In terms of power draw, noise, and cooling demands, the two options will be practically the same.

Forgive me if this sounds like our Llano review on replay, but it's hard to see where these Trinity APUs fit into the desktop PC landscape. Their 100W TDP disqualifies them from all-in-one systems, small-form-factor enclosures, and home theater PCs. Not being able to slide into those types of systems, where discrete graphics cards aren't practical, largely negates AMD's advantage in integrated graphics performance. The 65W version of the A10 or A8 would be workable in a larger HTPC case, but you'll be giving up performance in order to fit into that envelope—and it'll still draw 10W more at peak than the Core i3-3225. Perhaps in that scenario, if you planned to do some gaming at 720p, Trinity's faster graphics would be the deciding factor.

The only remaining landing place for these 100W APUs is a budget desktop PC—but again, the Core i3-3225 will give you better single-threaded performance and lower power draw than the A10-5800K for just a few bucks more. I'm having a hard time envisioning a system guide build where the A10 makes more sense than the Core i3. What's the concept? A very budget desktop PC in which the user does a small amount of gaming with non-casual titles? That needle is hard to thread.

At least there is a narrow opening for the A8-5600K at $100, since the Pentium G2120 is such a willing victim. If you just want a web-surf-itron or a Facebook-inator, a basic PC that's snappier than the desperately cheap Atom- and Brazos-based stuff, the A8-5600K could well be the CPU for you.

What I'd really like to see AMD do next is release some desktop Trinity variants geared for lower power envelopes, like 35W and 45W. The Socket FM2 platform's power draw at idle is impressively low. And in the world of slim enclosures, Mini-ITX motherboards, and iMac-style all-in-ones, Trinity would be playing to its strengths, not its weaknesses.

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