UPDATE 1-Elpida, Powerchip venture ekes profit in July-Sept

* Rexchip logs operating, net profits on stronger DRAM price

* First net profit in five qtrs

* Test unit Tera Probe also turns profitable (Adds background, details)

TOKYO, Oct 9 (Reuters) - Japanese PC memory maker Elpida Memory Inc 6665.T said on Friday its venture with Taiwan's Powerchip Semiconductor Corp (5346.TWO) turned profitable in July-September on rising prices of DRAM.

It is the first time the Taiwan firm Rexchip Electronics Corp, 52 percent owned by Elpida, has made operating and net profits in five quarters as dynamic random-access memory prices fell 80 percent in 2008 in a battered chip sector.

Elpida, which competes with South Korea's Samsung Electronics Co (005930.KS) and Hynix Semiconductor Inc (000660.KS), said in a statement that if the current recovery in chip prices continues, its profit will become more substantial.

"Profit levels are still not high, but the current strength of demand is encouraging," Elpida spokesman Michinari Tsurumaki said.

Elpida, which is smarting from seven straight quarters of losses, also said its Japanese chip test unit Tera Probe Inc turned profitable in the quarter just ended, thanks to demand for testing of mobile DRAM used in smartphones.

Other investors in Tera Probe include Taiwan's Powertech Technology Inc (6239.TW), U.S. module maker Kingston Technology Co and Japanese tester maker Advantest Corp (6857.T). (Reporting by Mayumi Negishi; Editing by Michael Watson)