<ARTICLE> 5
<RESTATED><F1>
<MULTIPLIER> 1,000

                                                                                            
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS                   YEAR
<FISCAL-YEAR-END>                          DEC-31-1999             DEC-31-1999             DEC-31-1999             DEC-31-1999
<PERIOD-START>                             JAN-01-1999             JAN-01-1999             JAN-01-1999             JAN-01-1999
<PERIOD-END>                               MAR-31-1999             JUN-30-1999             SEP-30-1999             DEC-31-1999
<CASH>                                          12,909                  12,598                  12,603                  21,043
<SECURITIES>                                    15,006                  14,209                  17,328                 186,440
<RECEIVABLES>                                   24,313                  32,834                  40,039                  47,110
<ALLOWANCES>                                     (596)                   (599)                   (595)                   (639)
<INVENTORY>                                     24,227                  25,716                  26,088                  28,410
<CURRENT-ASSETS>                                84,406                  92,975                 103,520                 289,373
<PP&E>                                          32,160                  32,634                  33,890                  36,328
<DEPRECIATION>                                (15,951)                (15,906)                (17,314)                (18,629)
<TOTAL-ASSETS>                                 113,456                 122,163                 134,642                 325,433
<CURRENT-LIABILITIES>                           18,323                  23,574                  25,758                  31,889
<BONDS>                                              0                       0                       0                 135,000
<PREFERRED-MANDATORY>                                0                       0                       0                       0
<PREFERRED>                                          0                       0                       0                       0
<COMMON>                                            29                      29                      30                      31
<OTHER-SE>                                      94,193                  97,607                 107,388                 156,958
<TOTAL-LIABILITY-AND-EQUITY>                   113,456                 122,163                 134,642                 325,433
<SALES>                                         36,419                  81,782                 137,408                 202,849
<TOTAL-REVENUES>                                36,419                  81,782                 137,408                 202,849
<CGS>                                           21,187                  46,280                  76,955                 110,647
<TOTAL-COSTS>                                   21,187                  46,280                  76,955                 110,647
<OTHER-EXPENSES>                                12,970                  27,886                  44,123                  62,876
<LOSS-PROVISION>                                     0                       0                       0                       0
<INTEREST-EXPENSE>                                  42                      98                     162                   1,430
<INCOME-PRETAX>                                  2,182                   7,581                  17,358                  30,876
<INCOME-TAX>                                       951                   3,060                   6,747                  11,741
<INCOME-CONTINUING>                              1,231                   4,521                  10,611                  19,066
<DISCONTINUED>                                       0                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0                       0
<CHANGES>                                            0                       0                       0                       0
<NET-INCOME>                                     1,231                   4,521                  10,611                  19,066
<EPS-BASIC>                                     0.04                    0.15                    0.36                    0.64
<EPS-DILUTED>                                     0.04                    0.15                    0.35                    0.62
<FN>
<F1> RESTATED PER POOLING MERGER OF ADVANCED ENERGY AND SEKIDENKO, INC. IN Q3
     2000
</FN>