BEIJING, April 17 -- Mao Yuhui, a Beijing civil servant, did not buy the new Corolla as planned when he got lucky in Beijing's car plate lottery. An incautious man, he put all his money into the Chinese stock market.

"The stock market is so hot, maybe in two weeks I can buy a Camry instead," he said. Mao invested 90,000 yuan (about 14,500 U.S. dollars) and expects to double his money. As of Thursday he was 20,000 yuan to the good.

Mao is one of millions of Chinese investors clinging to a rocketing market. All this week, the Shanghai Composite Index has set new high after new high. From April 7 and April 10, more than 1.68 million new accounts were opened in the A-share market. On April 12, a ban on multiple accounts was lifted, so each investor can now have up to 20 accounts.

The number of investors exceeded the capacity of the market data system. China Securities Depository and Clearing Corporation Limited reported delays in processing digital certificates on Tuesday, and many new investors, desperate to join the feeding frenzy, failed to have their accounts approved.

The Chinese stock market started rising rapidly in 2014 when it grew by 50 percent -- the fastest growth in Asia. This year has been no different with Shanghai climbing by over 25 percent so far and Shenzhen by about half as much.

The madness comes as quite a surprise, and a worry. China's GDPgrowth in Q1 was a mere 7 percent, down from 7.3 percent in last year's Q4. A stock market rising so precipitously against such an economic background should set alarm bells ringing. There is much talk of bubbles and risk.

Xiao Gang, chairman of the China Securities Regulatory Commission, warned on Thursday that new investors who lack experience of market turbulence should stay calm, and fully evaluate the risks of investment. "Don't follow blindly like sheep," he advised.

Stock market veteran Zhao Shucheng has bitter memories, shared by many investors, of 2007 and 2008 when the Shanghai Composite Index crashed from 6120 to 1665. Zhao lost about 200,000 yuan.

"We had a joke about the stock market at that time: you drive in with a Mercedes-Benz and walk out with nothing," Zhao said as he watched a screen in a stock trading hall in Beijing's Xicheng District. Unlike Mao Yuhui, he only invests one third of his money and is ready to sell at any time.

Some specialists and investors do not agree. Citibank recently burst a number of potential bubbles, claiming that there was no risk until market indices hit double current levels.

Sun Yu, chief China securities strategist at HSBC, believes that a more open capital market with less government control over IPO pricing means that now is the time for foreign investors to hit China's market.

Not all market rises are bubbles: government policy and national strategy have fueled this rise. Since the beginning of this year,innovation has been the watchword of China's leaders. "Makers" are the new economic heros and "Internet Plus" key to an innovation economy.

According to account registration data, many new investors were born in the 1980s and 1990s, with no experience of the carnage of seven years ago. They are more optimistic and have nontraditional views on investment.

Xiao Wu, an investor born in the 1980s, has an account with Orient Securities in Shanghai. He considers himself expert in technology, media and telecom.

"I am concerned about whether a company possesses core competence and innovative capabilities, or if it has the potential to expand along the industry chain, not profit to earnings ratios," he said.

Some commentators go even further. Yu Weiguo, a columnist at Sina.com, thinks the stock market is set to replace real estate as the new darling of national strategy. A booming market will nourish future backbone industries, he claimed, despite occasional capital bubbles.

"The stock market is a mechanism that encourages innovation. It draws in private capital and helps young people get a foothold in many new industries, some of which could be vital to the transition of China's economy," Yu added.

Another columnist, Xiang Xiaotian, echoed Yu's thought. "For China, if there is no bubble in the second-board market, then there is no start-up, no innovation, and no future for China's economy."