Toshiba Satellite A660D-ST2G01: AMD's Quad-Core Phenom II P920 Joins the Mobile Party

Toshiba A660D-ST2G01 General Performance

As one of the first up-to-date AMD notebooks to hit our labs in a long time, the Toshiba A660D certainly piqued our interest. Where will the quad-core P920 fall in regards to the competition? How much will battery life improve? How does gaming fare? You've got questions, and we've got the answers. Here's a recap of the pertinent details of our test system.

Starting off with PCMark Vantage and PCMark05, we get our first glimpse of the potential of the P920. Despite the lower clock speed, the P920 outpaces the Turion II M600 by 20% and the Athlon II M300 by 27% in Vantage. The gap is smaller in PCMark05, but that's obviously an old (outdated even) benchmark so we won't worry about it too much. That's the good news; the bad news is that Intel's slowest Core i3 processors are still faster in general application performance. The i3-330M with Intel HD Graphics is 20% faster, and the i5-430M with HD 5650 is 34% faster. The slow clock speed of the P920 just doesn't keep up in these types of workloads.

Peacekeeper shows the worst-case scenario where Intel's Turbo Boost is in full effect and the higher clocks of dual-core parts take front stage. On the AMD side, the M300 is 17% faster than the P920 and the M600 is 38% faster. Switch to Intel and the slowest i3-330M comes in 42% faster (ouch!), while the i5-430M is 54% faster. Heavily threaded tests don't do the P920 any favors either, as the i3-330M with Hyper-Threading still leads by a small amount in Cinebench SMP and x264 2nd pass. The only win for the P920 comes in the first pass of x264 encoding, where it's about 5% faster than the i3-330M.

What about the AMD quad-core versus Intel quad-core comparison? The ASUS G73Jh does come with a faster 5870 GPU, but even when we take that out of the picture the i7-720QM is clearly much faster than the P920. The gap is 50% in PCMark Vantage, and it goes up from there. The lead is 64% in Peacekeeper and 114% in the single-threaded Cinebench result, where Turbo Boost is in full effect. The lead in multi-core Cinebench is 64%, 2nd pass x264 is 63%, and the closest result is in the 1st pass x264 where the lead drops to just 19% (as memory and storage performance become bigger factors).

The P920 is certainly fast enough for most users, but the fact that a quad-core processor can't establish a lead over dual-core Intel parts even in multi-threaded tests is telling. Low power draws are good for battery life, but higher clock speeds are necessary to close the performance gap. We'd really like to see AMD put their Turbo Core technology from the desktop Phenom II X6 processors into their mobile parts, as the low 1.6GHz clock is definitely hurting performance in many tasks. In fact, there are a few instances where the overclocked SU7300 CULV processor (in the Alienware M11x) beats the P920. AMD does have some faster quad-core parts available, of course. N930 runs at 2.0GHz, which means it should be around 25% faster in CPU limited tasks, and the X920 BE runs at 2.30GHz, but those comes with 35W and 45 TDP, respectively. At lower loads those processors should use roughly the same power as the P920, but load power draw will be substantially higher.

The bottom line is that AMD's CPU cores could still use help, as clock for clock they're similar to the old Core 2 chips. Core 2 was available at speeds up to 3.07GHz dual-core and 2.53GHz quad-core, and even the fastest of those parts are surpassed by the midrange Core i3/i5/i7 parts. AMD is able to compete with Intel's old generation mobile hardware now, but that still means they're around 18 months behind. The result is that they need to sell at lower prices to stay relevant, and that's what they're doing.

Toshiba A660D-ST2G01 3DMark Performance

For those that like to compare 3DMarks, here are the results from the A660D (using the HD 5650 in all cases). Consider this a preview of the gaming performance on the next page.

The only other HD 5650 system we've tested to date is the Acer 5740G (which is, sadly, discontinued—though you can get the 7740G if you don't mind the 17" chassis). As mentioned already, that 5650 was clocked at 550MHz compared to 450MHz in the A660D, plus it used an i5-430M CPU. The result is a performance lead of anywhere from 6% (3DMark06) to 36% (3DMark05) over the A660D, but what we don't know for sure is if the limiting factor is the CPU or the lower GPU clock. Most likely it's some of each, so let's look at actual gaming performance and see where the chips fall.