Samsung
The logo of Samsung Electronics is seen at the company's headquarters in Seoul, South Korea on July 6, 2012. REUTERS/Lee Jae-Won/File Photo

Samsung and Tencent are now the world's top two performing large cap technology stocks, making waves in a crowded sector where big rivals like Apple and Alibaba have recently been having a very tough time. The companies have added around 30 billion dollars in market value in the past week alone. They are also both firmly in the race to be crowned Asia's most valuable company.

For Samsung, it's all about nailing the smartphone market — and that's exactly what it's doing, after years of struggle that left investors crying out for higher returns. Now, demand for the new Galaxy S7 is out-stripping supply. One analyst saying sales could hit the 15-million mark this year — nearly double the number of the previous model in 2015.

Tencent, meanwhile, is rapidly closing in on the world's top 10 biggest companies. Its popular messaging apps WeChat and Weixin have driven monthly user numbers up more than 30 percent, and major bets on mobile gaming - now the most valuable games market in the world - are paying off big time.

Investors seem largely upbeat, although some analysts have their red flags ready.

Samsung and Tencent have both been more volatile than the Asia tech sector as a whole, prompting the old-fashioned warning that "the higher they climb, the harder they fall."