The Asus M2-CROSSHAIR motherboard uses a lot of copper heatpipe-based thin fin heatsinks. The nVIDIA nForce 590 SLI chipset generates a fair share of heat, requiring more cooling than most chipset out there. Mostly though, the nForce northbridge and southbridge chipsets are cooled by a totally silent thermal solution - so there are no small fans to fail over time, no small fans to make noise, and no small fans to get clogged with dust.

The nForce 590 SLI MCP has a finless chunk of copper mounted on it, with a heatpipe snaking its way around slots and onboard devices towards the northbridge heatsink which is an extruded aluminum device. Two heatpipes connect the Northbridge heatsink to two large 28 fin copper heatsinks that are mounted directly on the processor's power supply MOSFETs.

The thin copper fin heatsinks on the MOSFETs surround the AMD AM2 socket so any exhaust airflow from the processor fan passes immediatly through their fins. It's important to remember that if water cooling is used here, you must replace the lost airflow with Asus' squirrel cage fan, or some other case fan or the chipsets may begin to overheat.

The additional fan that Asus includes with the motherboard is a quiet squirrel cage fan, it attaches to the copper fin heatsink directly. Once installed the fan are tightly secured and is a little hard to take off - so there is no worry of it coming loose. There is power for this fan in the area, so cable clutter is reduced. The processor fan has a dedicated 4-pin PWM compatible header to connect to.

The nVIDIA nForce 590 SLI chipset gets pretty hot under load, but in our experience with the Asus M2-CROSSHAIR we found it's passive chipset and VRM thermal solution quite effective at keeping these temperatures in check. The squirrel cage fan is generally quiet during operation.

External eSATA Device Support

eSATAII (aka external Serial ATA) support is one of the most exciting features to pop on motherboards recently. When it comes to external mass storage, bandwidth has always been an issue, and Serial ATA makes even IEEE 1394b's 800Mbps bandwidth look paltry by comparison. Asus has placed two external SATA (eSATA) ports on the rear I/O of the Asus M2-CROSSHAIR, just below the LCD Poster screen.

This connection uses a slightly modified SATA cable (not included), which is better suited to external connections. Standard internal Serial ATA cables are sufficient for internal connections, but SATA-IO governing body decided a while back that the external version should be a somewhat different format, thus creating the eSATA standard.

eSATA enclosures for hard drives are widely available, and the great thing is that hard drives connected over this standard are just as fast as internal devices. The connectors are hot swappable, so it makes adding and removing an massive external hard drive about as complex as pluging in a USB memory key. For anyone who as ever had to move Gig's of data over a USB cable, eSATA is simply awesome.