Hitachi releases water-cooled notebook PC

Hitachi Ltd. has announced the commercial launch of its water-cooled notebook PC, a 1.8GHz mobile Pentium 4-based machine which uses a patented Hitachi system to aid heat dissipation.

Most notebooks are cooled by air fans, and as processors have grown more powerful and begun to generate more heat, these fans have become more numerous, larger, and have needed to spin faster.

This has also meant that fans have become noisier and might not be suitable for use in places like libraries, Hitachi said.

The new Flora 270W Silent Model uses a water-based solution tank, instead of a fan or fans for cooling down the processor. Hitachi announced a working prototype using this technology in February.

"The efficiency of a water cooling system and the air cooling system are about the same but the biggest difference is the noise the latter creates," said Masayuki Akabane, a Hitachi spokesman.

The water-based solution runs through a flexible tube that is placed over the chips and absorbs heat. The heated water solution is then sent to the display part of the notebook to be stored in a tank where it cools down.

The solution can last for more than five years, the flexible tube can circulate the solution over 20,000 times and the pump works for more than 44,000 hours, the statement said.

Plastic panels separate these water-cooling elements from high-voltage areas, in case of a solution leak from the cooling system. The Tokyo company also offers a three-year guarantee service for the product.

The new products are slightly thicker than existing air-cooled Flora models, in order to show the tank at the back of the LCD (liquid crystal display) panel and hence differentiate the water-cooled machine, Akabane said. The tank also be hidden, he said.

The products are equipped with a 1.8GHz mobile Intel 4 processor, 128M bytes of RAM, a 20G-byte hard disk drive and a 15-inch (37.5-centimeter) color TFT (thin film transistor) LCD (liquid crystal display), and are priced at