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                                                                  EXHIBIT 4.3.5

                                FOURTH AMENDMENT
                                     TO THE
                           THIRD RESTATED AND AMENDED
                      PUBLIC SERVICE COMPANY OF NEW MEXICO
                             PERFORMANCE STOCK PLAN

         THIS FOURTH AMENDMENT is made by the Public Service Company of New
Mexico effective upon the implementation of a holding company structure pursuant
to which PNM Resources, Inc. will become the parent holding company for Public
Service Company of New Mexico through a mandatory share exchange. The mandatory
share exchange presently is scheduled to occur on December 1 [31], 2001.

         WHEREAS, Public Service Company of New Mexico originally adopted the
Public Service Company of New Mexico Performance Stock Plan (the "Plan") as of
July 1, 1993 to provide certain key employees with an incentive to put forth
maximum effort to achieve a pattern of sustained growth for Public Service
Company of New Mexico;

         WHEREAS, the Plan has been restated three times, with the most recent
restatement being effective as of March 10, 1998;

         WHEREAS, the restated Plan has been amended three times, most recently
effective December 10, 2000;

         WHEREAS, Public Service Company of New Mexico reserved the right to
amend the Plan pursuant to Section 10.1 of the Plan; and

         WHEREAS, Public Service Company of New Mexico now desires to amend the
Plan to: (i) change the name of the Plan; (ii) make PNM Resources, Inc. the
sponsor of and participating employer in the Plan; and (iii) designate Public
Service Company of New Mexico as a participating employer.

         NOW, THEREFORE, Public Service Company of New Mexico does hereby amend
the Plan as follows:

         1.       The name of the Plan is hereby amended to read as follows:


                           THIRD RESTATED AND AMENDED
                   PNM RESOURCES, INC. PERFORMANCE STOCK PLAN

               (FORMERLY, THE PUBLIC SERVICE COMPANY OF NEW MEXICO
                             PERFORMANCE STOCK PLAN)

         2.       Article I of the Plan is hereby amended in its entirety to
read as follows:

                    The purpose of the PNM Resources, Inc. Performance Stock
         Plan (the "Plan") is to increase the proprietary interests in the
         Company of certain key employees with the intent of (i) fostering a
         strong incentive for such individuals to put forth maximum effort to
         achieve a pattern of sustained growth of the Company, and to perform in
         the best interests of the Company, its shareholders, customers and
         employees, (ii) retaining individuals who will put forth such efforts,
         and (iii) attracting the best available individuals to fulfill those
         positions in the future. The Plan was originally approved by the
         shareholders of Public Service Company of New Mexico on May 25, 1993,
         and was effective on July 1, 1993. The Plan was first amended on
         February 23, 1994, and was restated and amended effective January 1,
         1996 (the "First Restated and Amended Plan"). In 1997, the First
         Restated and Amended Plan was amended. The Second Restated and Amended
         Plan was approved and became effective on March 10, 1998 (the "Second
         Restatement"). Also, effective on March 10, 1998, Public Service
         Company of New Mexico made certain technical

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         corrections to the Second Restatement and, for administrative
         convenience, embodied the technical corrections in the form of a
         restatement (the "Third Restatement").

                    Effective on completion of a mandatory share exchange, PNM
         Resources, Inc. will become the parent holding company for Public
         Service Company of New Mexico and the Plan is hereby amended to reflect
         this new holding company structure.

         3.       Section 2.7 of the Plan is hereby amended in its entirety to
read as follows:

                     2.7    "COMPANY" means PNM Resources, Inc., or any
       affiliate of the Company that is authorized by the Board to adopt the
       Plan and which has adopted the Plan. Affiliates that adopted the Plan
       prior to the effective date of the Fourth Amendment with the consent of
       the Public Service Company of New Mexico board of directors, including
       Public Service Company of New Mexico, shall continue to participate in
       the Plan.

         4.       Section 2.23 of the Plan is hereby amended in its entirety to
read as follows:

                     2.23   "PLAN" means the PNM Resources, Inc. Performance
       Stock Plan, as adopted herein. The Plan was formerly known as the Public
       Service Company of New Mexico Performance Stock Plan.

         5.       Section 2.25 of the Plan is hereby amended in its entirety to
read as follows:

                     2.25   "PRESIDENT" shall mean the President of PNM
       Resources, Inc.

         6.       The purpose of this Fourth Amendment is to transfer
sponsorship of the Plan to PNM Resources, Inc. from the Public Service Company
of New Mexico. Any other provisions of the Plan which are inconsistent with this
transfer of sponsorship are hereby amended to the extent necessary to accomplish
this transfer.

         7.       This Fourth Amendment changes the name and sponsorship of the
Plan but the Plan is ongoing. Any individuals or entities serving in positions
of responsibility with respect to the Plan shall continue to serve as such,
subject to the provisions of the Plan. Similarly, any policies or procedures
previously adopted by such individuals or entities shall continue in full force
and effect.

         8.       This Fourth Amendment shall only amend the provisions of the
Plan referred to above, and those provisions not amended hereby shall be
considered in full force and effect. By the execution of this Fourth Amendment,
PNM Resources, Inc. agrees to serve as the sponsor of and a participating
employer in the Plan.

         IN WITNESS WHEREOF, Public Service Company of New Mexico has caused
this Fourth Amendment to be executed as of this 31 day of December, 2001.

                      PUBLIC SERVICE COMPANY OF NEW MEXICO


                      By: /s/ Alice A. Cobb
                         -------------------------------------------
                                   Senior Vice President, People
                                   Services and Development
                                   ---------------------------------


                      ACCEPTED:

                      PNM RESOURCES, INC.


                      By: /s/ Alice A. Cobb
                         -------------------------------------------
                                   Senior Vice President, People
                                   Services and Development
                                   ---------------------------------