X-bit labs

ASUS U3S: Two Notebooks in a Single Case (page 7)

Category: Mobile

by Alexander Britvin

[ 03/16/2008 | 10:26 AM ]

Configuration

The ASUS U3S is based on an Intel Core 2 Duo T7500 processor with a clock rate of 2.2GHz (65nm Merom core with 4 megabytes of shared L2 cache). The FSB frequency is 800MHz.

The Core 2 Duo T7500 supports Intel’s 64-bit extensions to the x86 architecture and also features Intel Wide Dynamic Execution technology which means more decoders and execution units in the CPU core.

Besides Intel’s traditional Enhanced SpeedStep technology that gives the notebook’s software and BIOS the control over the CPU frequency multiplier (to reduce it under low loads), this CPU supports Dynamic Power Coordination (the power consumption of the cores can be independently adjusted depending on the current load; one core may even slip into Deep Sleep mode with the lowest power consumption possible), Dynamic Cache Sizing (unused segments of the CPU cache can be turned off to save power), and FSB Frequency Switching (the FSB clock rate is automatically lowered at low loads). We couldn’t spot the effect from the latter technology with the appropriate tools, yet the test results are indicative of its benefits. For more information about Intel’s Core 2 Duo processors refer to our review called "Santa Rosa + Vista: Three Notebooks Reviewed" or to the manufacturer’s website.

This implementation of the Santa Rosa platform also incorporates an Intel PRO/Wireless 4965AGN adapter and an Intel Crestline GM965 chipset. The 965 series chipsets support a FSB frequency of 800MHz. The GM965 offers a PCI Express x16 interface for an external graphics card and also features an integrated graphics core called Intel Graphics Media Accelerator X3100. Connected to the North Bridge via a special-purpose Direct Media Interface, the South Bridge (ICH8-M) supports three Serial ATA-300 ports, ten USB 2.0 ports and Intel High Definition Audio. It also offers six PCI Express x1 lanes to connect external devices. For more information about the platform, visit the manufacturer’s website.

GMA X3100 is the first graphics core from Intel to support shaders on the GPU. As a result, the new integrated chipset features improved performance and compatibility with 3D applications, particularly with Windows Vista’s Aero interface. The X3100 can also support DirectX 10 using the recently released driver. The new core is clocked at a frequency of 500MHz and incorporates 8 unified shader processors for 3D rendering as well as for video playback acceleration. Thanks to them, the X3100 provides hardware acceleration and post-processing for video content in MPEG-2 and WMV9 formats. The core doesn’t support the new compression standards H.264 and VC-1 (Blu-ray and HD-DVD), though. Besides higher performance, the new graphics core has acquired more advanced power-saving features, mostly meant to reduce the consumption of the LCD panel which is the main power consumer in a notebook together with the CPU. The X3100 supports Display Power Saving Technology 3.0 that is automatically adjusts the brightness and contrast of the screen to reduce power consumption yet keep the image quality high. The Display Refresh Rate Switching technology can be used to reduce the refresh rate of the screen when the notebook works on its battery.

The Crestline GM965 chipset provides the PCI Express x16 interface ASUS engineers connected a discrete graphics core GeForce Go 8400M G to. It is accompanied with 128 megabytes of dedicated graphics memory and can also be allotted a portion of system memory for a total of 896MHz. The GPU is manufactured on 0.08-micron tech process that ensures a lower power draw in comparison with 0.11- and 0.09-micron chips. That’s why the junior model in the 8xxx series is specially intended for thin and light notebooks. It supports DirectX 10 Shader Model 4.0, PureVideo technology for high-quality HD video playback and PowerMizer technology for efficient power management. You can refer to the manufacturer’s website for details about the GeForce Go 8400M G. The basic specs of the GeForce Go 8400 series are listed in the table below:

The notebook comes with a Hitachi HTS541616J9SA00 hard disk drive (2.5” form-factor, 5400rpm spindle rotation speed, 160GB capacity, SATA interface).

The ASUS U3S works with DDR2-667 SDRAM, the fastest memory available on the Santa Rosa platform. The single accessible slot is occupied by a 1GB module. A 512MB module is installed on the mainboard. The memory works in dual-channel mode because some of it is used by the GPU. The maximum amount of memory the notebook supports is 2560MB.

We measured the temperature of the hottest spots on the notebook’s surfaces with an infrared thermometer after it had worked for half an hour in PCMark 2005 (the ambient temperature remained constant at 23°C during this test) and got the following numbers:

• LCD panel – 40°C
• Keyboard – 32°C
• Bottom panel – 35°C
• Vent hole – 35°C

So, the notebook is rather cool even under load. The following table lists the specs of the ASUS U3S: