NEW YORK, (

TheStreet

) --

Dell's

(DELL) - Get Report

ongoing tumble has bounced out its phone and tablet chief Ron Garriques, as the PC giant seeks to simplify its approach to mobile products.

With few successes to point to, Garriques will leave Dell at the end of January after nearly four years on the job. Prior to Dell, Garriques had been the mobile device chief at

Motorola

(MOT)

until early 2007.

During Garriques' tenure, Dell dropped to third in PC sales and watched rivals like

Apple

(AAPL) - Get Report

,

Palm

and

Google

(GOOG) - Get Report

usher in a new generation of mobile phones.

Even

Hewlett-Packard

(HPQ) - Get Report

finally came around to the mobile computing trend and acquired Palm to gain some headway.

Dell, under Garriques introduced a Google Android-powered 5-inch tablet called the Streak in August, but sales never really took off. Dell also developed a

Microsoft

(MSFT) - Get Report

Windows Phone 7 device called

Venue that has also not proven

yet to be a blockbuster.

The move comes ahead of

Dell's release of third quarter earnings

after the bell Thursday.

Dell shares are down 7% so far this year amid concerns that the company is not gaining any ground on its turnaround plan.

--Written by Scott Moritz in New York.>To contact this writer, click here: Scott Moritz, or email: scott.moritz@thestreet.com.To follow Scott on Twitter, go to http://twitter.com/MoritzDispatch.>To send a tip, email: tips@thestreet.com.