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                                 EXHIBIT 10 (u)

                            THIRD AMENDMENT AGREEMENT

     This Third Amendment Agreement made as of the 23rd day of April, 2002, by
and between Pinnacle Data Systems, Inc. (the "Borrower") and KeyBank National
Association (the "Lender"):

     WHEREAS, Borrower and Lender are parties to a certain Loan Agreement dated
August 10, 2000, as it may from time to time be amended, supplemented or
otherwise modified (the "Loan Agreement");

     WHEREAS, Borrower and Lender desire to amend the Loan Agreement by
modifying a certain financial covenant thereof, and

     WHEREAS, each term used herein shall be defined in accordance with the Loan
Agreement.

     NOW, THEREFORE, in consideration of the premises and of the mutual
covenants herein and for other valuable considerations, Borrower and Lender
agree as follows:

     I. The Loan Agreement is hereby amended by deleting the existing financial
     covenant "B" contained in the "Financial Covenants" section in its entirety
     and replacing it with the following:

     B) Maintain a Total Debt to Tangible Net Worth ratio of less than or equal
        to 2.50 to 1.00 which shall be tested on a quarterly basis based upon
        the financial statements of Borrower for the most recently completed
        fiscal quarter.

     2. Borrower hereby represents and warrants to Lender that (a) Borrower has
the legal power and authority to execute and deliver this Third Amendment
Agreement; (b) officials executing this Third Amendment Agreement have been duly
authorized to execute and deliver the same and bind Borrower with respect to the
provisions hereof, (c) the execution and delivery hereof by Borrower and the
performance and observance by Borrower of the provisions hereof do not violate
or conflict with the organizational agreements of Borrower or any law applicable
to Borrower or result in a breach of any provision of or constitute a default
under any other agreement, instrument or document binding upon or enforceable
against Borrower; (d) no Event of Default exists under the Loan Agreement, nor
will any occur immediately after the execution and delivery of the Third
Amendment Agreement or by the performance or observance of any provision hereof;
(e) neither Borrower (nor any subsidiary) has any claim or offset against, or
defense or counterclaim to, any of Borrower's (or any subsidiary's) obligations
or liabilities under the Loan Agreement or any Related Documents, and Borrower
(and each subsidiary) hereby waives and releases Lender from any and all such
claims, offsets, defenses and counterclaims of which Borrower (and any
subsidiary) is aware, such waiver and release being with full knowledge and
understanding of the circumstances and effect thereof and after having consulted
legal counsel with respect thereto, and (f) this Third Amendment Agreement

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constitutes a valid and binding obligation of Borrower in every respect,
enforceable in accordance with its terms.

     3. Each reference that is made in the Loan Agreement or any other writing
shall hereafter be construed as a reference to the Loan Agreement as amended
hereby. Except as herein otherwise specifically provided, all provisions of the
Loan Agreement shall remain in full force and effect and be unaffected hereby.

     4. The rights and obligations of all parties hereto shall be governed by
the laws of the State of Ohio.

     5. JURY TRIAL WAIVER. BORROWER AND LENDER WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR
OTHERWISE, BETWEEN BORROWER AND LENDER, ARISING OUT OF, IN CONNECTION WITH,
RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED BETWEEN THEM IN
CONNECTION WITH THIS AGREEMENT OR ANY NOTE OR OTHER INSTRUMENT, DOCUMENT OR
AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE TRANSACTIONS
RELATED THERETO. THIS WAIVER SHALL NOT IN ANY WAY AFFECT, WAIVE, LIMIT, AMEND OR
MODIFY LENDER'S ABILITY TO PURSUE REMEDIES PURSUANT TO ANY CONFESSION OF
JUDGMENT OR COGNOVIT PROVISION CONTAINED IN ANY NOTE OR OTHER INSTRUMENT,
DOCUMENT OR AGREEMENT BETWEEN BORROWER AND LENDER.

Address:    Pinnacle Data Systems, Inc.      PINNACLE DATA SYSTEMS, INC.
            6600 Port Road
            Groveport, Ohio 43125
            Attn: Michael R. Sayre           By: /s/ Michael R. Sayre
                                                 --------------------
                                             Its: Michael R. Sayre, Executive VP
Address:    KeyBank National Association     KEYBANK NATIONAL ASSOCIATION
            88 East Broad Street
            Columbus, Ohio 43215
            Attn: Roger D. Campbell          By: /s/ Mary L. Patton, VP
                                                 ----------------------
                                             Its: Mary L. Patton, Vice President

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