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                                                                   EXHIBIT 10.47
                                 AMENDMENT NO. 2
                                       TO
                            STOCK PURCHASE AGREEMENT
                                       AND
                             SENIOR PROMISSORY NOTES

         THIS AMENDMENT NO. 2 TO STOCK PURCHASE AGREEMENT AND SENIOR PROMISSORY
NOTES (the "Amendment") is dated as of October 3, 1996, between Earl M. Pearlman
("Pearlman"), William E. Decker ("Decker") and the William E. Decker Trust (the
"Trust," and collectively with Pearlman and Decker, "Sellers") and MTI
Technology Corporation, a Delaware corporation (the "Purchaser").

     A. Sellers and Purchaser entered into that certain Stock Purchase Agreement
(as amended by Amendment No. 1 thereto, the "Agreement") dated as of April 2,
1995 relating to the sale of the capital stock of National Peripherals, Inc.;
that certain Senior Promissory Note by Purchaser in favor of Trust in the amount
of $715,000 dated as of April 2, 1995 (the "Decker Note"); and that certain
Senior Promissory Note by Purchaser in favor of Pearlman in the amount of
$1,285,000, dated as of April 2, 1995 (the "Pearlman Note").

     B. Subsequent to the entering into of the Agreement, Pearlman and Decker
have agreed to accept broader management responsibilities for the Purchaser
beyond the original intended scope of Pearlman's and Decker's duties.

     C. Sellers and Purchaser desire to amend the Agreement, the Decker Note and
the Pearlman Note as set forth herein. Capitalized terms not otherwise defined
herein shall have the meaning ascribed to them in the Agreement.

         NOW, THEREFORE, in consideration of the mutual covenants hereinafter
set forth, the parties to this Amendment hereby agree as follows:

     1. Contingent Payments. Section 1.4 of the Agreement is amended in its
entirety as follows:

                  1.4      Contingent Payments.

                                    (a) As part of the Purchase Price, Purchaser
         shall make three (3) guaranteed annual payments to Sellers in the
         manner and at the times provided in Section 1.4(b) and Section 1.5.
         Each such annual payment shall be in the amount (the "Annual Payment
         Amount") of One Million Dollars ($1,000,000) in the aggregate. Payment
         of the three Annual Payments is unconditional and is not subject to the
         attainment of any profit, revenue or other goal or condition. Only the
         Final Payment described in subsection (d) below, shall be determined by
         reference to a formula.
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                                    (b) Except as provided in subparagraphs (e)
         - (i) below or in the event of any dispute as to the calculation
         thereof under Section 1.5 (in which event payment shall be made within
         fifteen (15) days of the calculation of the Annual Payment Amount
         becoming final), each payment of the Annual Payment Amount shall be
         made by Purchaser to Sellers within sixty (60) days after the end of
         each fiscal year following the Closing Date, beginning in April 1996,
         net of any offset pursuant to Article X, below; provided that the first
         period of calculation shall commence on the Effective Date hereof. Each
         Seller shall be entitled to the percentage of the Annual Payment Amount
         shown in Exhibit "A" hereto.

                                    (c) Subject to any offset pursuant to
         Article X, below, which for the purpose of this subparagraph (c) shall
         be treated as if received by Sellers, to the extent that the aggregate
         Annual Payment Amounts made pursuant to this Section 1.4 prior to or
         concurrent with the Final Payment (as defined below), if any, are less
         than Two Million Dollars ($2,000,000), the Final Payment shall be
         increased in an amount equal to such shortfall (the "Shortfall").

                                    (d) As part of the Purchase Price, Purchaser
         shall make a final payment (the "Final Payment") in the manner provided
         in Section 1.5, within sixty (60) days after the end of the fiscal year
         ended April 1998, except as provided in subparagraphs (e) - (i), below,
         or in the event of any bona fide dispute as to the calculation thereof
         under Section 1.5 (in which event payment shall be made within fifteen
         (15) days of the calculation of the Final Payment becoming final). The
         Final Payment shall equal One Million Dollars ($1,000,000)in the event
         that the total aggregate Open Systems Revenue (as defined below) for
         the three fiscal years commencing fiscal 1996 shall meet or exceed
         Eighty Four Million Dollars ($84,000,000), less any reduction required
         by Section 1.3(g) above or offset pursuant to Article X, below. "Open
         Systems Revenue" shall mean all revenue of Purchaser related to sales
         of products that will perform in an open systems environment.

                                    (e) Notwithstanding anything to the contrary
         herein, Purchaser's obligations to make any Contingent Payments (as
         defined below) to a Seller in the event that any Seller's employment
         with Purchaser terminates shall be as set forth in this subsection (e):

                                          (i) In the event any Seller's
                  employment is terminated by Purchaser for Cause (as defined in
                  such Seller's Employment agreement), Seller shall be entitled
                  to no Contingent Payments earned on or after his termination,
                  except for his portion of the Shortfall, if any.

                                          (ii) In the event any Seller's
                  employment is terminated by reason of death or disability (as
                  defined in such Seller's Employment agreement), Seller or his
                  estate shall be entitled to all remaining Contingent Payments
                  earned, if any.

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                                          (iii) In the event any Seller's
                  employment is terminated by such Seller voluntarily, Seller
                  shall be entitled to no Contingent Payments earned on or after
                  his termination.

                                          (iv) In the event any Seller's
                  employment is terminated by Purchaser without Cause, Seller
                  shall be entitled to all remaining Contingent Payments earned,
                  if any.

     For purposes of this Section 1.4, Contingent Payments shall be earned as of
the last day of the fiscal year on which the payment of such amount is based.

                           (f) The Annual Payments and the Final Payment as
determined under this Section 1.4 are hereafter referred to as the "Contingent
Payments."

                           (g) If an Event of Default (as defined in the Note)
occurs under any Note, such Seller shall be entitled to receive an amount equal
to his percentage (as shown in Exhibit "A" hereto) of the Shortfall less the
amount of aggregate Contingent Payments made to all Sellers as of the date of
such default, which amount will be paid to such Seller within fifteen (15)
business days.

                           (h) If Purchaser discontinues its non-DEC storage
business, Sellers shall be entitled to receive all Contingent Payments that
would otherwise have been paid after such discontinuation as if the percentage
in (d) above had been one hundred percent (100%), which amount will be paid
Sellers within fifteen (15) business days.

                           (i) If Purchaser sells its non-DEC storage business
to an unaffiliated third party and such third party shall fail to expressly
assume in writing Purchaser's obligations to make Contingent Payments hereunder,
Sellers shall be entitled to receive all Contingent Payments that would
otherwise have been paid after such discontinuation as if the percentage in (d)
above had been one hundred percent (100%), which amount will be paid Sellers
within fifteen (15) business days.

         2. Senior Promissory Notes. Section 7.1(d) of each of the Decker Note
and the Pearlman Note is amended in its entirety as follows:

                     (d) Maker discontinues its non-DEC storage business or
                  sells substantially all the assets thereof to an unaffiliated
                  third party; and

     3.           Miscellaneous.

                  3.1 Except as specifically provided in Sections 1 and 2, the
Agreement, the Decker Note and the Pearlman Note have not been amended or
modified and are hereby confirmed.


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                  3.2 This Amendment may be executed in counterparts, each of
which shall constitute one and the same instrument.


                  3.3 The parties intend that this Amendment (and the Agreement,
Amendment No. 1 to the Agreement, the Decker Note and the Pearlman Note) shall
be the final expression of their agreement with respect to the subject matter
hereof and may not be contradicted by evidence of any prior or contemporaneous
agreement. The parties further intend that this Agreement (and the Agreement,
Amendment No. 1 to the Agreement, the Decker Note and the Pearlman Note)
constitute the complete and exclusive statement of the parties of their
agreement and that no extrinsic evidence whatsoever may be introduced in any
judicial, administrative, or other legal proceeding involving this Amendment.

     The parties have caused this Amendment to be duly executed as of the date
first written above.

                         PURCHASER:

                         MTI Technology Corporation,
                         a Delaware corporation
                     
                         By: /s/ Dale R. Boyd
                            ---------------------------------------------------
                               Title:  Vice President & Chief Financial Officer
                                       ----------------------------------------
                     
                         SELLERS:
                     
                         /s/ Earl M. Pearlman 
                         -------------------------------------------------------
                         Earl M. Pearlman

                         /s/ William E. Decker
                         -------------------------------------------------------
                         William E. Decker
                     
                     
                         William E. Decker Trust
                     
                         By: /s/ William E. Decker 
                            ----------------------------------------------------
                            William E. Decker,
                            Sole Trustee and Settlor
              
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