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                                                                   Exhibit 10.15

                                                               Execution Version

                          GSL INDUSTRIAL PARTNERS, L.P.
                           5858 WESTHEIMER, SUITE 800
                              HOUSTON, TEXAS 77057

                                 March 8, 2006

Suntron GCO, LP
2401 West Grandview Road
Phoenix, Arizona 85023
Attn: Hargopal (Paul) Singh

     Re: Earnest Money Contract dated effective as of December 27, 2005 (the
         "Initial Contract"), by and between GSL INDUSTRIAL PARTNERS, L.P., as
         buyer ("Buyer"), and SUNTRON GCO, LP, as seller ("Seller"), regarding
         the sale and purchase of approximately 36 acres of developed land, plus
         an additional approximately 7.5 acres of undeveloped land, located at
         1111 Gillingham Lane, Sugar Land, Fort Bend County, Texas (the
         "Property")

Dear Mr. Singh:

     Reference is hereby made to the Initial Contract, as amended by that
certain letter agreement dated February 2, 2006, executed by Seller and Buyer
(the "First Letter Agreement"). All capitalized terms used in this second letter
agreement (the "Second Letter Agreement") and not otherwise defined shall have
the same meanings as set forth in the Initial Contract as modified by the First
Letter Agreement. On and after the date hereof, all references to the "Contract"
shall mean the Initial Contract as modified by the First Letter Agreement and
this Second Letter Agreement.

     For and in consideration of the mutual covenants and agreements contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, Seller and Buyer hereby agree as follows:

     (1) SALES PRICE. Section 4 of the Contract shall be, and hereby is,
amended, replaced and superseded to read in its entirety as follows:

     "4.  SALES PRICE. The Buyer will pay the Seller the amount of NINETEEN
          MILLION THREE HUNDRED THOUSAND AND NO/100 DOLLARS ($19,300,000)
          ("SALES PRICE"), as follows:

          (a)  Seventeen Million Eight Hundred Thousand and No/100 Dollars
               ($17,800,000) of the Sales Price (the "INITIAL PAYMENT"), shall
               be paid in cash at Closing; and

          (b)  One Million Five Hundred Thousand and No/100 Dollars ($1,500,000)
               of the Sales Price (the "DEFERRED PORTION OF THE SALES PRICE"),
               shall be paid by Buyer to Seller subject to and in accordance
               with the terms of this Section 4(b).

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Suntron GCO, LP
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               (i) Beginning on April 1, 2007, and subject to the satisfaction
               of the Financial Test (as such term is defined below), Buyer
               shall make payments to Seller, on a fiscal quarter basis, of
               $200,000 each (each, a "DEFERRED PAYMENT"), until the Deferred
               Portion of the Sales Price has been paid in full. All provisions
               of the Contract dealing with the Deferred Portion of the Sales
               Price shall survive the Closing and shall remain in effect until
               all of the Deferred Portion of the Sales Price has been paid to
               Seller. For purposes of this Section 4(b), the term "FINANCIAL
               TEST" shall consist of two (2) different financial tests that are
               based on the financial results of Seller's parent Suntron
               Corporation, a Delaware corporation ("SUNTRON"), as follows:

                         (A) The first test is based on and is a test of
                    Suntron's aggregate EBITDA margin (on a consolidated basis)
                    (being the percentage that results from dividing EBITDA by
                    net sales) for the most recent period consisting of four (4)
                    consecutive fiscal quarters. For purposes hereof, Suntron's
                    "EBITDA" is defined as Net Income or Loss (determined in
                    accordance with U.S. generally accepted accounting
                    principles consistently applied ("GAAP")) plus Interest
                    Expense, Income Taxes, Depreciation and Amortization. For
                    purposes of this calculation, Suntron's GAAP Net Income or
                    Loss will be further modified to exclude (to the extent the
                    following have been included in the calculation of EBITDA):
                    (I) up to $5 million of cumulative cash restructuring costs
                    actually incurred, (II) all non-cash stock compensation,
                    impairment and restructuring charges, (III) up to $1,500,000
                    of legal fees actually incurred related to the Applied
                    Material litigation more particularly described in Suntron's
                    periodic filings with the U. S. Securities and Exchange
                    Commission, and (IV) the earnings impact (whether positive
                    or negative) of any settlement in the Applied Material
                    litigation.

                         (B) The second test is referred to as the Free Cash
                    Flow ("FCF") test. This test is based on and is a test of
                    the ratio of Suntron's FCF to Suntron's "Cash Interest
                    Expense" for the most recent period consisting of four (4)
                    consecutive fiscal quarters. FCF for this calculation is
                    defined as EBITDA from the financial test described in
                    subsection (A) above less Suntron's net cash payments for
                    capital expenditures (computed by taking the difference
                    between cash paid for capital expenditures and cash proceeds
                    from sales of capital assets as reported in Suntron's cash
                    flow statement under GAAP). The amount of net cash payments
                    for capital expenditures that are included in any 4 quarter
                    period shall be the lesser of (I) $2,700,000 and (II) the
                    net amount actually paid by Suntron during such period. For
                    purposes hereof, "Cash Interest Expense" is defined as
                    Suntron's accrual basis interest expense determined in
                    accordance with GAAP less (I) amortization of debt issuance
                    costs and (II) interest expense that is "payable in kind"
                    pursuant to the terms of Suntron's debt agreements.

               The Financial Test is considered to be satisfied if any one of
               the following results are achieved:

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Suntron GCO, LP
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                         (X) Suntron's EBITDA margin is equal to at least 4.0%
                    for the most recent period consisting of four (4)
                    consecutive fiscal quarters; or

                         (Y) Suntron's FCF ratio is equal to at least 2.0 to 1.0
                    for the most recent period consisting of four (4)
                    consecutive fiscal quarters; or

                         (Z) Suntron's EBITDA margin is equal to at least 3.0%
                    and Suntron's FCF ratio is equal to at least 1.5 to 1.0 for
                    the most recent period consisting of four (4) consecutive
                    fiscal quarters.

               (ii) Buyer shall make a Deferred Payment to Seller on or before
               the date that is fifteen (15) days after Buyer has received
               certified financial calculations from Seller demonstrating
               compliance by Suntron with the Financial Test for the required
               time period in relation to such payment. Such written
               certifications of the financial calculations shall be made and
               certified by Suntron's Chief Financial Officer and shall include
               detailed calculations of the applicable Financial Test, provided
               Buyer shall have the right to request reasonable documentation
               which supports such calculations and to request other
               clarification related to such calculations. In the event that the
               requirements of the Financial Test are not met by Suntron for any
               particular period, then Buyer shall not be obligated to make any
               more Deferred Payments to Seller unless and until Suntron
               thereafter meets the Financial Test. Interest shall accrue on the
               unpaid portion of the Deferred Portion of the Sales Price at a
               rate equal to six and one-half percent (6.5%) per annum,
               compounded quarterly, provided that (A) such interest shall
               accrue and shall not be paid to Seller until all of the Deferred
               Portion of the Sales Price has been paid by Buyer to Seller in
               accordance with the terms hereof and (B) Buyer and Seller agree
               that if the loan from Buyer's first lien lender requires that
               Buyer pay an interest rate other than 6.5% per annum, the actual
               rate that Buyer pays from time to time on such loan shall be
               substituted for the rate set forth herein.

               (iii) In addition to the foregoing, and without regard to whether
               Seller is meeting the Financial Test, at any time that (A) the
               aggregate amount of (I) the unpaid portion of the Deferred
               Portion of the Sales Price, plus (II) the amount remaining
               drawable under the Supplemental LOC (as such term is defined in
               the Lease) (collectively, the "WITHHELD FUNDS"), exceeds (B) the
               Applicable Rent Balance (as such term is defined in the Lease),
               then Buyer shall, within ten (10) business days after Buyer's
               receipt of written request from Seller, pay to Seller out of the
               unpaid portion of the Deferred Portion of the Sales Price (plus
               any accrued but unpaid interest thereon) the amount, if any, by
               which the Withheld Funds exceed the Applicable Rent Balance, but
               not to exceed the remaining unpaid portion of the Deferred
               Portion of the Sales Price (plus any accrued but unpaid interest
               thereon).

               (iv) In addition, at any time after the date that is forty-two
               (42) months after the Commencement Date of the Lease (as such
               term is defined in the Lease), Suntron has achieved the Financial
               Test for eight (8) consecutive quarters, and provided that there
               is no Event of Default by Seller then existing at the time of
               Seller's request or Buyer's funding, Buyer shall, within ten (10)
               business days

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Suntron GCO, LP
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               after Buyer's receipt of written request from Seller, pay to
               Seller any portion of the Deferred Portion of the Sales Price
               (plus any accrued but unpaid interest thereon) that remains
               outstanding and unpaid as of such date.

               (v) On the date that is seven (7) years after the Closing Date,
               and provided that the Lease has not been terminated or the leased
               premises permanently repossessed by Buyer, whether or not the
               Lease is terminated, prior to such date, Buyer shall pay to
               Seller any portion of the Deferred Portion of the Sales Price
               (plus any accrued but unpaid interest thereon) that remains
               outstanding and unpaid as of such date.

               (vi) Notwithstanding any provision of this Contract to the
               contrary, Buyer shall not be obligated to make any payments to
               Seller towards the Deferred Portion of the Sales Price if there
               exists at the time such payment would otherwise be due (A) any
               monetary or payment Event of Default under the Lease, or (B) any
               non-monetary Event of Default under the Lease, which non-monetary
               Event of Default is reasonably expected to have an adverse affect
               to Buyer or the Property in the amount of $100,000 or more. Upon
               the cure of any such Event of Default, however, unless the Lease
               has been terminated or the leased premises permanently
               repossessed by Buyer, whether or not the Lease is terminated, any
               payment that was delayed due to the existence of the Event of
               Default shall be payable within ten (10) business days after
               Buyer's receipt of written request therefor from Seller."

     (2) APPLICATION OF EARNEST MONEY. The third sentence of Section 5 of the
Contract shall be, and hereby is, amended, replaced and superseded to read in
its entirety as follows:

     "At Closing, the Earnest Money and any interest earned thereon will be
     applied to the Initial Payment."

     (3) NO LIENS. Section 10(a)(1) of the Contract shall be, and hereby is,
amended, replaced and superseded to read in its entirety as follows:

     "(1) With no liens, assessments, or Uniform Commercial Code or other
          security interests against the Property which will not be satisfied
          out of the Initial Payment; and"

     (4) CLOSING PAYMENT. Paragraph 2(a) of ATTACHMENT IV of the Contract shall
be, and hereby is, amended, replaced and superseded to read in its entirety as
follows:

     "(a) the Initial Payment, subject to prorations and other adjustments as
          may be set forth herein;"

     (5) LEASE. The form of the Lease attached as EXHIBIT "C" to the Contract
shall be, and hereby is, amended, replaced and superseded by the form of the
Lease attached hereto as EXHIBIT "C"-REPLACEMENT.

     (6) INSPECTION PERIOD. Paragraph 4 of the First Letter Agreement is hereby
modified by the following: Seller and Buyer agree that the Inspection Period,
and Buyer's right to

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Suntron GCO, LP
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terminate the Contract by the delivery of the Inspection Notice, shall be and
hereby is extended until one (1) business day after the later of (a) the date of
the final platting of the Property in accordance with the provisions of
paragraph 1 of the First Letter Agreement; (b) the date on which Seller has
notified Buyer of the completion of the repairs and replacements to the Property
and provided Buyer with confirmation of the transferability of the Roof
Warranties, both as provided for in paragraph 3 of the First Letter Agreement.
The Closing shall occur no earlier than three (3) business days after the end of
the Inspection Period.

     (7) APPROVAL OF BUYER'S FINANCIAL PARTNER. Seller and Buyer acknowledge and
agree that the obligations of Buyer under the Contract are subject to the
approval of such transactions by Buyer's prospective financial partner, AEW
Capital Management, L.P. ("AEW"). If AEW has not approved the transactions
contemplated by the Contract by March 20, 2006, then Buyer shall have the right,
exercisable by written notice delivered by Buyer to Seller no later than 5:00 pm
Houston, Texas time on March 22, 2006, to terminate the Contract. Upon any such
termination, the Earnest Money shall be returned to Buyer free and clear of all
rights and claims of Seller with respect thereto, and neither Buyer nor Seller
shall have any further rights or obligations hereunder (except for matters
expressly stated in the Contract to survive termination).

     (8) CLOSING DATE.

     (a) Seller and Buyer agree that the Closing shall occur simultaneously with
the closing and funding of Suntron's proposed refinancing of Suntron's existing
senior credit facility with Citicorp USA, Inc. with a new senior credit facility
provided to Suntron by US Bank ("SUNTRON'S REFINANCING"); provided that the
Closing shall occur no earlier than March 23, 2006 (in the event the actual
closing and funding of Suntron's Refinancing occurs prior to such date) and not
later than March 31, 2006.

     (b) Notwithstanding the foregoing, if Suntron's Refinancing has not
occurred by March 31, 2006, either party shall have the right to extend the
deadline for the occurrence of Suntron's Refinancing until May 31, 2006, by
giving written notice of such extension to other party. Further if Suntron's
Refinancing has not occurred by May 31, 2006, then either party shall have the
right at any time thereafter to terminate the Contract by giving written notice
of termination to the other party and the Earnest Money shall be refunded to
Buyer.

     (c) Seller and Buyer agree to execute and deliver in escrow with the Title
Company all documents and instruments required to effect the Closing within
three (3) business days following the end of the Inspection Period.

     (d) Notwithstanding anything in this Paragraph 8 to the contrary, Buyer
shall not be obligated to deliver the Initial Payment, and the Closing of the
Contract shall not occur, until the actual closing and funding of Suntron's
Refinancing.

     (9) SUNTRON BOARD APPROVAL. Seller and Buyer acknowledge and agree that the
effectiveness of this Second Letter Agreement is conditioned on the approval of
the Board of Directors of Suntron.

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Suntron GCO, LP
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     (10) ARBITRATION. In the event there is a dispute between Buyer and Seller
as to (i) whether Seller has met the Financial Test for any period or (ii) any
other matters related to the payment to Seller of the Deferred Portion of the
Sales Price, Buyer and Seller agree to resolve such dispute by utilizing the
arbitration process (the "ARBITRATION PROCESS") set forth in this paragraph. In
the event there is a dispute between Buyer and Seller as to whether Seller has
met the Financial Test for any period or is otherwise qualified to receive a
payment from the Deferred Portion of the Sales Price, Buyer and Seller shall
meet to immediately resolve that matter in good faith and as expeditiously as
possible. If that matter cannot be resolved within ten (10) days after the
applicable due date for the Deferred Payment in dispute, then an arbitrator from
the list of arbitrators of the American Arbitration Association's Houston, Texas
office shall be jointly selected by Seller and Buyer, and that arbitrator shall
be unaffiliated with both Seller and Buyer and shall have at least five years
experience as an arbitrator (the "ARBITRATOR"). If Seller and Buyer cannot
mutually agree on the Arbitrator within five (5) business days, then the
Arbitrator shall be appointed by the American Arbitration Association. After
being duly appointed, the Arbitrator shall hold a hearing to determine the
question submitted (the "ARBITRATION"). At the Arbitration, the Real Estate
Industry Arbitration Rules of the American Arbitration Association then in
effect shall govern, including the Expedited Procedures. The Arbitration shall
commence within fifteen (15) days following appointment of the Arbitrator unless
a different time is specified in the Expedited Rules then in effect. Further,
the Arbitrator shall have the right to retain a nationally recognized accounting
firm (or other accounting firm mutually acceptable to Seller and Buyer), which
is independent of both Seller and Buyer, to assist the Arbitrator in analyzing
financial information. Within ten (10) days after the Arbitration, the
Arbitrator shall issue a decision in writing and in duplicate (the "ARBITRATION
RULING"), one counterpart thereof to be delivered to each of Seller and Buyer.
The Arbitration Ruling shall be binding, final and conclusive on Seller and
Buyer, and may be entered in any court having jurisdiction. The costs of the
Arbitration shall be borne by the party against whom the question so submitted
is resolved, unless otherwise expressly provided in the Arbitration Ruling (such
matter being an issue on which the Arbitrator is granted discretion to apportion
based on the equities of the specific situation). Each party shall pay on
request by the American Arbitration Association or Arbitrator all up-front costs
of the Arbitration that are required to be prepaid. If either party fails to pay
its share of the up-front costs of arbitration within ten (10) days after the
American Arbitration Association or Arbitrator has notified such party that its
fifty percent (50%) initial share thereof is due, and within an additional
period of ten (10) days after the other party's written demand, then the
Arbitrator shall make its ruling against the party who failed to pay such costs.
Nothing herein contained shall preclude either Seller or Buyer from seeking any
injunctive relief.

     (11) OFFSET RIGHT OF SELLER. If an Arbitrator has determined that a payment
for the Deferred Portion of the Sales Price is due to Seller from Buyer, and
Buyer fails to make such payment within ten (10) days following notice of the
Arbitrator's decision, then Seller shall be entitled to exercise the offset
rights described in Section II of Exhibit "G" of the Lease.

     Except as amended hereby, the Contract remains in full force and effect in
accordance with its original terms. Telecopy delivery of this Second Letter
Agreement signed by each party to the other shall be binding and effective the
same as if an original signed copy has been delivered by each party to the
other. This Second Letter Agreement may be executed in multiple

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Suntron GCO, LP
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counterparts, each of which shall be considered an original, and all of which
together shall constitute one and the same document.

                                      * * *

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Suntron GCO, LP
Page 8 of 8


     If you have any questions or comments with respect to any of the foregoing,
please do not hesitate to contact me.

                                        Sincerely yours,

                                        BUYER:

                                        GSL INDUSTRIAL PARTNERS, L.P.,
                                        a Texas limited partnership

                                        By: GSL Partners GP, LLC, a Texas
                                            limited liability company,
                                            its general partner


                                        By: /s/ WELCOME W. WILSON, SR.
                                            ------------------------------------
                                            Welcome W. Wilson, Sr.,
                                            Chairman and Chief
                                            Executive Officer

AGREED TO AND ACCEPTED
this _______ day of March, 2006:

SELLER:

SUNTRON GCO, LP,
a Texas limited partnership

By: Rodnic LLC, a Texas limited
    liability company,
    its general partner


By: /s/ JAMES A. DORAN
    ---------------------------------
    James A. Doran,
    Chief Financial Officer