Sony VAIO Z review: Portability, meet Power
As is the case with our reviews, here are some details about the hardware used in the assembly of Sony's VAIO Z notebook, as provided by software tools such as CPU-Z and GPU-Z.
If you take a closer look at the detailed specifications listed on the screenshot of GPU-Z, you would realize that there is more to the Power Media Dock that meets the eye. While most graphics cards, be it mobile or desktop grade, usually run off PCIe 2.0 x16, we realized that Sony's implementation of delivering data to and from the external AMD Mobility Radeon HD 6650M graphics card, while seemingly connected to a PCIe 2.0 x16 interface in the Power Media Dock, is actually transferring data at PCIe 2.0 x4 speeds. This tells us that Sony must be running PCIe 2.0 x4 over Light Peak in its implementation.
Even then, Sony's implementation appears to be somewhat flawed. Based on some information we have managed to gather from an analysis of the VAIO Z posted by another website*, it would seem that users are only capable of obtaining a maximum of 1.25GB/s of bandwidth from the VAIO Z and the Power Media Dock; this is significantly lesser than the 2GB/s which PCIe 2.0 x4 is supposed to deliver. This suggests that a significant chunk of bandwidth is probably lost to overheads (probably due to the graphics card, optical drive, a USB 3.0 port, a USB 2.0 port and a Gigabit Ethernet port sharing all the four lanes), and while it is still significantly more powerful than Intel's built-in GPU in the i7-2620M processor, the bottleneck imposed on the system by the crippled bandwidth is definitely going to rear its ugly head in graphics-intensive tasks and benchmarks. More on this later.
For an ultra-portable notebook such as the Sony VAIO Z, it is only fair to claim that battery life is going to be a major consideration for potential customers, if only because of the growing need for a mobile professional to possess a portable computing device which is capable of delivering close to full day's worth of juice on a single charge. Unlike the previous review, we tried out a new method of gauging battery life by making use of a .BAT file to keep track of the amount of time that has elapsed while we ran various tasks on the machine at the same time.
The result was that the Sony VAIO Z managed to return an uptime of up to 157 minutes of continuous video playback (or 2 hours 37 minutes) of a 1080p video clip. When we repeated the test by having PC Mark Vantage loop the Productivity and Web Page Rendering tests to simulate a heavy productivity workload, the VAIO Z's battery was able to sustain the notebook for 94 minutes (or 1 hour 34 minutes) before cutting out. While it is definitely not really 'full-day computing' battery life, remember that more than two and a half hours of continuous video playback is lot, and the 94 minutes of uptime under a synthetic benchmarking tool could well translate to approximately three to five hours of total battery uptime under typical use with power saving features turned on.
We have raved about how Sony was able to squeeze in a whopping 1080p full high-definition (HD) resolution into a 13-inch display, but have you wondered how the panel actually performs? Well, we have taken the liberty of finding out, and the results are as follow:
For the most part, the VAIO Z's liquid crystal display is illuminated in a fairly consistent manner, although one can make out the signs of some significant bleeding at the panel's bottom. However, we would go as far as to say that this is largely a non-issue. if only because that area is typically obscured by the Windows task bar and the status panel of most maximized applications; this makes it unlikely to affect an average user who has no concept of backlight bleeding or uneven screen illumination.
We have no doubt in our minds that the external AMD Mobility Radeon HD 6650 graphics card provided by the Power Media Dock will be more than capable for HD video playback, so we decided to perform the video playback test with the i7-2620M's built-in GPU core instead. However, considering how Intel's onboard graphics solutions since the GMA950 has demonstrated that they have the capability to deal with HD video playback without significant performance issues, we were really not surprised to see the i7-2620M's onboard GPU handle our 1080p video playback test with minimal dropped frames or jitters.
Futuremark PCMark 7
For the most part, any notebook that features Intel's Sandy Bridge platform is usually more than up to the task for handling most of today's computing needs such as web surfing, HD movie playback, Flash acceleration and even the occasional light casual gaming. Therefore, we are not amazed to discover that Sony's new VAIO Z notebook returned a score of 4043 points upon running the full PCMark 7 test suite on it when disconnected from the Power Media Dock.
What did capture our interest, however, was the fact that repeating the benchmark with the Power Media Dock attached to the VAIO Z actually produced a score that was lower than the previous test. After some research, we concluded that such behaviour is perfectly normal and to be expected; this is because the data transfer speeds found in Intel's Quick Path Interconnect interface used in its processor is significantly faster than what Light Peak is technically capable of (25.6GBps vs 20Gbps).
Futuremark 3DMark 11
Remember how we spoke about Sony's implementation of Light Peak seemingly imposing a bottleneck of sorts on the VAIO Z notebook? Turns out that such suspicions were well-founded after all, if the scores returned for 3DMark 11 are of any indication. Despite being more powerful than the NVIDIA GT540M graphics card used in previous notebook reviews, the VAIO Z with its external AMD Mobility Radeon HD 6650M graphics card was only able to deliver scores that were slightly higher that those found in our previous notebook reviews.
*As claimed by Anandtech