Sunnyvale resident Terry Liu, Quanta's marketing manager, recalls that after seeing the way a cookie company's products crumbled under testing, engineers suggested either a tougher package or a tougher cookie.

"They went with a tougher cookie," Liu says.

Quanta's engineers have given similar advice over the years to NASA scientists testing space shuttle equipment and high-tech companies testing computer parts. The Santa Clara-based lab celebrated its 20th anniversary earlier this year.

Liu estimates that Quanta has served more than 2,000 customers since his father, Dr. Hong Liu, founded the lab in 1985. He says Quanta's customer base mirrors the diversity of Silicon Valley.

"You get to see lots of different products and meet lots of engineers," Liu says. "We hear about a lot of things before they become consumer products, and we get to break things."

The idea behind product testing, Liu says, is to find the failure point before the customer does. Companies tend to put a very small portion of their research and development budgets toward testing, he says.

"That's what we're trying to teach: Put a little bit into quality control and get much higher margins," Liu says. "People are willing to pay for quality."

This is the lesson Quanta engineers are trying to impart to their counterparts in China, where the company has seven testing facilities. Liu senior, a Chinese native, has made several trips back to his home country to give seminars on proper product-testing methods.

"We're still having a problem making them understand the importance of testing," he says, adding that U.S. companies that outsource research and development to the Far East are suffering as a result. "It's very difficult to find a testing lab in China."

In addition to the basics of product testing, Quanta's Chinese employees are learning how to use a new piece of equipment developed by Hong Liu. The production line environmental stress screener (PLESS) is designed to "shake and bake" computer components while they're being made, performing vibration and temperature tests simultaneously. During testing, components are held aloft by a steady air stream.

"We got the idea from our air hockey table," Quanta's founder says.

The inspiration may have come from a piece of recreational equipment, but the Lius say the practical applications of PLESS are revolutionary.

"Testing that now takes three days can be done in less than half an hour," Terry Liu says.

The system is also a money-saver, Hong Liu says.

"For every dollar we spend, we save $80" in testing, he says. "If you screen out problems while a PC board is still on the production line, your reliability goes way up, and you spend only a few dollars."

Quanta lays claim to being the largest product-testing lab in Northern California. Hong Liu says his lab's growth can be attributed to customer service as well as innovative equipment.

"We treat our customers as friends," he says. "We have lots of repeat business. Everyone here is a degreed engineer. We know what we're doing."