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                                                                   EXHIBIT 11.01
 
                              ESS TECHNOLOGY, INC.
 
                      COMPUTATION OF NET INCOME PER SHARE
                    (IN THOUSANDS, EXCEPT PER SHARE AMOUNTS)
 


                                                                  YEAR ENDED DECEMBER 31,
                                                              -------------------------------
                                                               1996        1997        1998
                                                              -------    --------    --------
                                                                            
Weighted average common shares..............................   37,702      39,953      40,955
Weighted average incremental common equivalent shares:
  Common stock(2)...........................................    3,886          --          --
  Cheap stock(2)............................................       --          --          --
                                                              -------    --------    --------
Total weighted average common and common equivalent
  shares....................................................   41,588      39,593      40,955
                                                              =======    ========    ========
Net income (loss)...........................................  $21,626    $(10,866)   $(28,016)
                                                              =======    ========    ========
Net income (loss) per share.................................  $  0.52    $  (0.27)   $  (0.68)
                                                              =======    ========    ========

 
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(1) This Exhibit should be read in conjunction with Note 1 of Notes to
    Consolidated Financial Statements.
 
(2) Earnings per share is computed using the weighted average number of common
    and common equivalent shares ("weighted average shares") outstanding during
    the period. Common equivalent shares consist of the Company's common stock
    issuable upon exercise of stock options (using the treasury stock method),
    except when antidilutive. Common stock issued and stock options granted
    subsequent to July 31, 1994 through October 5, 1995, (the date of the
    initial public offering) have been included in the calculation of weighted
    average shares outstanding as if they were outstanding for reporting periods
    occurring between these dates. The Company used the treasury stock method
    and the initial public offering price of $15.00 per share for these
    calculations.