<PAGE>
                                                                 EXHIBIT 4(g)(3)


                     SECOND AMENDMENT AGREEMENT AND CONSENT

         This Second Amendment Agreement and Consent dated as of August 22, 2000
(this "Amendment and Consent") is among Reliant Energy Resources Corp., a
Delaware corporation (formerly known as NorAm Energy Corp., a Delaware
corporation) ("Borrower"), the lenders parties hereto ("Banks"). The Bank of
Nova Scotia, as Issuing Bank, and Citibank, N.A., as agent ("Agent") under the
Revolving Credit Agreement dated as of March 31, 1998, as amended by the
Amendment Agreement dated as of March 23, 1999, among the Borrower, the Agent
and the Banks (as previously amended, the "Credit Agreement"). Terms defined in
the Credit Agreement shall be used in this Amendment and Consent with their
defined meanings unless otherwise defined herein.

                              W I T N E S S E T H:

         WHEREAS, in order to consummate the Unregco IPO Transaction (as defined
below) and to make certain other changes in connection therewith, the Borrower
has requested that the Agent and the Banks enter into this Amendment and Consent
with respect to the Credit Agreement as set forth herein;

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration the receipt and sufficiency of which is hereby
acknowledged, the parties hereto hereby agree as follows:

         1. DEFINED TERMS. The following terms used in this Amendment and
Consent have the meanings set forth below:

                  (a) "Reliant Energy" means Reliant Energy, Incorporated, a
                  Texas corporation.

                  (b) "Reliant Energy Services" means Reliant Energy Services,
                  Inc., a Delaware corporation.

                  (c) "Unregco" means a to-be-formed Wholly-Owned Subsidiary of
                  Reliant Energy which, after the consummation of the Unregco
                  IPO Transaction, will be the parent company of a significant
                  portion of Reliant Energy's unregulated businesses.

                  (d) "Unregco IPO Transaction" means collectively, the related
                  transactions whereby:

                           (i) certain of the contracts of Reliant Energy
                           Retail, Inc. representing business in states other
                           than Texas, Minnesota and Wisconsin are sold to third
                           parties;

                           (ii) all of the capital stock of Reliant Energy
                           Retail, Inc. and certain other Subsidiaries of the
                           Borrower is contributed by the Borrower to Reliant
                           Energy Services;



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<PAGE>

                           (iii) (A) all of the capital stock of Reliant Energy
                           Services is distributed by the Borrower to Reliant
                           Energy, and then contributed by Reliant Energy to
                           Unregco. (B) Unregco Merger Sub is merged into
                           Reliant Energy Services with Reliant Energy Services
                           as the surviving corporation of the merger, and with
                           the surviving corporation of the merger becoming a
                           Wholly-Owned Subsidiary of Unregco and the Borrower
                           receiving shares of Reliant Energy common stock as
                           consideration of the merger, or (C) pursuant to some
                           other corporate transaction Reliant Energy Services
                           becomes a Wholly-Owned Subsidiary of Unregco;

                           (iv) the contribution of all of the assets of Reliant
                           Energy's electricity retail operations to Unregco or
                           a Wholly-Owned Subsidiary of Unregco;

                           (v) the contribution of all of the capital stock of
                           Reliant Energy's non-Borrower unregulated businesses,
                           including (A) Reliant Energy Power Generation, Inc.,
                           a Delaware corporation, (B) Reliant Energy Net
                           Ventures, Inc., a Delaware corporation, (C) Reliant
                           Energy Communications, Inc., a Delaware corporation
                           and (D) certain other Subsidiaries of Reliant Energy,
                           by Reliant Energy to Unregco; and

                           (vi) the issuance and sale of up to 20% of the common
                           stock of Unregco in an initial public offering of
                           such stock,

                  and any changes to such steps of the Unregco IPO Transaction
                  as described in the Texas Public Utility Commission's Final
                  Order in Docket 21956 (so long as the resulting structure does
                  not have, in the opinion of the Agent, a material adverse
                  impact on the Banks).

                  (e) "Unregco Merger Sub" means a yet to be formed Wholly-Owned
                  Subsidiary of Unregco which will merge with and into Reliant
                  Energy Services.

         2. CONSENT. The parties hereto hereby agree that, subject to compliance
at all times with the Borrower's covenant to maintain the financial ratio set
forth in Section 8.02(a) of the Credit Agreement both before and after giving
effect to the Unregco IPO Transaction, but notwithstanding any other provisions
of the Loan Documents (including, without limitation, Sections 7.01(h), 8.02(c),
and 8.02(g) of the Credit Agreement) that might otherwise prohibit the Unregco
IPO Transaction, the Unregco IPO Transaction shall be permitted consistent with
the definition thereof, and no Default or Event of Default shall be deemed to
have occurred under the Loan Documents solely as a result thereof.

         3. AMENDMENT OF CREDIT AGREEMENT. Section 7.01(h) of the Credit
Agreement is hereby amended by adding the following phrase at the end of the
first sentence before the period: "or pursuant to any other transaction that is
expressly permitted by the terms of any other provision of this Agreement."



                                      -2-
<PAGE>

         4. REPRESENTATIONS AND WARRANTIES; DEFAULT. After effect to the
amendments and consents contained herein, (a) the Borrower hereby confirms,
reaffirms and restates that each of the representations and warranties set forth
in Article VII of the Credit Agreement are true and correct in all material
respects (except for (1) those representations and warranties or parts thereof
that, by their terms expressly relate solely to a specific date, in which case
such representations and warranties are true and correct in all material
respects as of such specific date; and (2) the representation and warranty set
forth in clause (i) of Section 7.01(j)) on and as of the date hereof as though
made on and as of the date hereof; provided that each reference in such Article
VII to "this Agreement" shall be deemed to be a reference both to this Amendment
and Consent and to the Credit Agreement as previously amended and as amended and
affected by this Amendment and Consent and (b) no Default or Event of Default
has occurred or is continuing.

         5. EXPENSES. The Borrower agrees to pay or reimburse the Agent for all
of its out-of-pocket costs and reasonable expenses incurred in connection with
this Amendment and Consent, any other documents prepared in connection herewith
and the transactions contemplated hereby, including, without limitation, the
reasonable fees and disbursements of counsel to the Agent.

         6. NO CHANGE. Except as expressly amended and affected hereby, all of
the terms and provisions of the Credit Agreement and the other Loan Documents
(as may have been previously amended) are and shall remain in full force and
effect. The amendments and consents contained herein shall not constitute in
amendment or waiver of the Credit Agreement or the other Loan Documents except
as expressly set forth herein.

         7. EFFECTIVENESS. This Amendment and Consent shall become effective as
of August 22, 2000 once the Agent shall have received counterparts of this
Amendment and Consent, duly executed and delivered by the Borrower, the Agent
and the Majority Banks. On and after said effective date, the term "Agreement"
as used in the Credit Agreement, the other Loan Documents executed in connection
therewith, and any other instrument, document, or writing furnished to the
Banks, the Agent, or the Co-Agents by the Borrower shall mean the Credit
Agreement, as amended and affected hereby.

         8. COUNTERPARTS. This Amendment and Consent may be executed in any
number of counterparts by the parties hereto, each of which counterparts when so
executed shall be an original, but all the counterparts shall together
constitute one and the same instrument.

         9. GOVERNING LAW. THIS AMENDMENT AND CONSENT SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.



                  [Remainder of page left blank intentionally]



                                      -3-
<PAGE>




                  IN WITNESS WHEREOF, the parties hereto have caused this
Amendment and Consent to be duly executed and delivered by their proper and duly
authorized officers as of the date first above written.

                                       BORROWER:

                                       RELIANT ENERGY RESOURCES CORP.
                                       (formerly known as NorAm Energy Corp.)



                                       By:      /s/ Marc Kilbride
                                           -------------------------------------
                                                Marc Kilbride
                                                Treasurer


                                       AGENT:

                                       CITIBANK, N.A., as Agent



                                       By:      /s/ Anita J. Brickell
                                          --------------------------------------
                                                Authorized Officer

                                       ISSUING BANK:

                                       THE BANK OF NOVA SCOTIA



                                       By:      /s/ M.D. Smith
                                          --------------------------------------
                                                Authorized Officer



                                      -4-
<PAGE>




                                       BANKS:


                                       CITIBANK, N.A.


                                       By:      /s/ Anita J. Brickell
                                          --------------------------------------
                                                Authorized Officer


                                       BARCLAYS BANK PLC


                                       By:
                                          --------------------------------------
                                                Authorized Officer



                                       THE FIRST NATIONAL BANK OF CHICAGO


                                       By:
                                          --------------------------------------
                                                Authorized Officer


                                       BANK OF AMERICA, N.A. (FORMERLY
                                       NATIONSBANK, N.A.)


                                       By:      /s/ Claire Liu
                                          --------------------------------------
                                                Authorized Officer


                                       THE BANK OF NEW YORK


                                       By:      /s/ Nathan S. Howard
                                          --------------------------------------
                                                Authorized Officer



                                      -5-
<PAGE>




                                       THE BANK OF TOKYO-MITSUBISHI, LTD.,
                                         HOUSTON AGENCY


                                       By:
                                          --------------------------------------
                                                Authorized Officer

                                       THE CHASE MANHATTAN BANK


                                       By:      /s/ Robert W. Matthews
                                          --------------------------------------
                                                Authorized Officer


                                       CREDIT SUISSE FIRST BOSTON


                                       By:/s/ Thomas G. Muoio   /s/Lalita Advani
                                          --------------------------------------
                                                Authorized Officer


                                       DEPOSIT GUARANTY NATIONAL BANK


                                       By:
                                          --------------------------------------
                                                Authorized Officer


                                       FLEET NATIONAL BANK


                                       By:      /s/ Rita M. Cahill
                                          --------------------------------------
                                                Authorized Officer


                                       TORONTO DOMINION (TEXAS), INC.


                                       By:      /s/ Mark A. Baird
                                          --------------------------------------
                                                Authorized Officer



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<PAGE>




                                       UBS AG, NEW YORK BRANCH


                                       By:
                                          --------------------------------------
                                                Authorized Officer


                                       THE BANK OF NOVA SCOTIA


                                       By:      /s/ M.D. Smith
                                          --------------------------------------
                                                Authorized Officer


                                       WESTDEUTSCHE LANDESBANK
                                         GIROZENTRALE, NEW YORK BRANCH


                                       By:      /s/ Duncan M. Robertson
                                          --------------------------------------
                                                Authorized Officer


                                       By:      /s/ Anthony Alessandro
                                          --------------------------------------
                                                Authorized Officer


                                       MELLON BANK, N.A.


                                       By:      /s/ Roger E. Howard
                                          --------------------------------------
                                                Authorized Officer

                                      -7-