<PAGE>



                                   MCSI, INC.
                                 AS THE BORROWER

                                       AND

                     THE FINANCIAL INSTITUTIONS NAMED HEREIN
                                   AS LENDERS

                               NATIONAL CITY BANK
                     AS A LENDER AND AS DOCUMENTATION AGENT

                         PNC BANK, NATIONAL ASSOCIATION
                       AS A LENDER, THE SWING LINE LENDER
                            A LETTER OF CREDIT ISSUER
                           AND AS ADMINISTRATIVE AGENT


                              ---------------------

                                AMENDMENT NO. 10
                                   DATED AS OF
                               SEPTEMBER 27, 2000
                                       TO
                      AMENDED AND RESTATED CREDIT AGREEMENT
                                   DATED AS OF
                                DECEMBER 1, 1998

                              ---------------------




<PAGE>

                                AMENDMENT NO. 10
                                       TO
                      AMENDED AND RESTATED CREDIT AGREEMENT


          THIS AMENDMENT NO. 10 TO AMENDED AND RESTATED CREDIT AGREEMENT, dated
as of September 27, 2000 ("THIS AMENDMENT"), among:

               (i)   MCSI, INC., a Maryland corporation which is the successor
          by merger to Miami Computer Supply Corporation, an Ohio corporation
          (herein, together with its successors and assigns, the "BORROWER");

               (ii)  the financial institutions listed on the signature pages
          hereof (the "LENDERS");

               (iii) NATIONAL CITY BANK, a national banking association, as a
          Lender and as Documentation Agent; and

               (iv)  PNC BANK, NATIONAL ASSOCIATION, a national banking
          association, as a Lender, the Swing Line Lender, a Letter of Credit
          Issuer and as Administrative Agent (the "ADMINISTRATIVE AGENT") for
          the Lenders under the Credit Agreement:

          PRELIMINARY STATEMENTS:

          (1)  The Borrower, the Lenders named therein, and the Administrative
Agent entered into the Amended and Restated Credit Agreement, dated as of
December 1, 1998, as amended by Amendment No. 1 thereto, dated as of March 31,
1999, Amendment No. 2 thereto, dated as of April 19, 1999, Amendment No. 3
thereto, dated as of August 13, 1999, Amendment No. 4 thereto, dated as of
August 31, 1999, Amendment No. 5 thereto, dated as of December 20, 1999,
Amendment No. 6 thereto, dated as of January 10, 2000, Amendment No. 7 thereto,
dated as of February 4, 2000, Amendment No. 8 thereto, dated as of April 30,
2000 and Amendment No. 9 thereto, dated May 31, 2000 (as so amended, the "CREDIT
AGREEMENT"; with the terms defined therein, or the definitions of which are
incorporated therein, being used herein as so defined).

          (2)  Pursuant to Amendment No. 7 to Amended and Restated Credit
Agreement, dated as of February 4, 2000 ("AMENDMENT NO. 7"), the Credit
Agreement was amended to provide, among other things, for a temporary increase
in the Total General Revolving Commitment from $160,000,000 to $175,000,000, and
the Lenders made General Revolving Loans to the Borrower reflecting usage of
such temporary increase (such General Revolving Loans reflecting such usage are
referred to herein as "PRIOR BRIDGE LOANS").

          (3)  Pursuant to Amendment No. 8 to Amended and Restated Credit
Agreement, dated as of April 30, 2000 ("AMENDMENT NO. 8"), the Credit Agreement
was amended to extend the maturity of the Prior Bridge Loans and such temporary
increase in the Total General Revolving Commitment from April 30, 2000 to May
31, 2000, to increase the interest rate margins applicable to the Prior Bridge
Loans, and otherwise to amend certain provisions of the Credit Agreement, all as
more fully set forth therein.

          (4)  Pursuant to Amendment No. 9 to Amended and Restated Credit
Agreement, dated as of May 31, 2000 ("AMENDMENT NO. 9"), the Credit Agreement
was amended to extend the maturity of the Prior Bridge Loans and such temporary
increase in the Total General Revolving Commitment from May 31, 2000 to June 30,
2000, all as more fully set forth therein.

          (5)  The Prior Bridge Loans having been paid in full, the parties
hereto desire to amend the Credit Agreement to provide for a temporary increase
in the Total General Revolving Commitment from $160,000,000 to $170,000,000, and
otherwise to amend certain provisions of the Credit Agreement, all as more fully
set forth below.

          NOW, THEREFORE, the parties hereby agree as follows:
          1.   AMENDMENTS, ETC.

          1.1. TEMPORARY INCREASE IN TOTAL GENERAL REVOLVING COMMITMENT, ETC.
(a) Effective only during the period from September 27, 2000 through the earlier
of (i) the first borrowing by any Foreign


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Subsidiary under the Canadian credit facility proposed to be made available by
The Toronto Dominion Bank, as previously described to the Lenders, or (ii)
November 30, 2000 (such earlier date, the "TEMPORARY INCREASE END DATE"), the
Total General Revolving Commitment shall be increased from $160,000,000 to
$170,000,000, and the General Revolving Commitments of the Lenders set forth in
Annex I to the Credit Agreement shall be amended to reflect the following:

<TABLE>
<CAPTION>

Lender                                 General Revolving Commitment
------------------------------------   ----------------------------
<S>                                    <C>
PNC Bank, National Association         $26,562,500
National City Bank                     $26,562,500
Key Corporate Capital Inc.             $26,562,500
Bank One, Indiana, N. A.               $26,562,500
Firstar Bank, N. A.                    $26,562,500
The Huntington National Bank           $26,562,500
The Provident Bank                     $10,625,000
                                       ------------
         TOTAL                         $170,000,000
                                       ============
</TABLE>

          (b)  For the avoidance of doubt, it is noted that the Borrower has the
right to make permanent reductions in the amount of the Total General Revolving
Commitment in accordance with the provisions of section 4.2(c) of the Credit
Agreement. If as of 5:00 P. M. (local time at the Notice Office of the
Administrative Agent) on November 30, 2000 (or any earlier Temporary Increase
End Date), the Total General Revolving Commitment shall not previously have been
permanently reduced to $160,000,000 or less by a voluntary and permanent
reduction made in accordance with the provisions of section 4.2(c) of the Credit
Agreement, THEN effective as of such time the Total General Revolving Commitment
shall be automatically and permanently reduced from $170,000,000 to
$160,000,000, and Annex I to the Credit Agreement shall be amended to reflect
the reduced General Revolving Commitments of the Lenders as follows:

<TABLE>
<CAPTION>

Lender                                 General Revolving Commitment
---------------------------------      ----------------------------
<S>                                    <C>
PNC Bank, National Association         $25,000,000
National City Bank                     $25,000,000
Key Corporate Capital Inc.             $25,000,000
Bank One, Indiana, N. A.               $25,000,000
Firstar Bank, N. A.                    $25,000,000
The Huntington National Bank           $25,000,000
The Provident Bank                     $10,000,000
                                       ------------
         TOTAL                         $160,000,000
                                       ============
</TABLE>

          (c)  To the extent that General Revolving Loans outstanding under the
Credit Agreement reflect a usage of the temporary increase in the Total General
Revolving Commitment from $160,000,000 to $170,000,000 effected by this
Amendment (General Revolving Loans reflecting such usage are referred to herein
as "BRIDGE LOANS"), THEN notwithstanding anything to the contrary contained in
the Credit Agreement, (i) the Applicable Prime Rate Margin for Bridge Loans
which are Prime Rate Loans shall be 250 basis points, and (ii) the Applicable
Eurodollar Margin for Bridge Loans which are Eurodollar Loans shall be 450 basis
points.

          (d)  The only Interest Period which shall be available for a Bridge
Loan which is a Eurodollar Loan is an Interest Period of one month, subject to
Continuation for additional Interest Periods as provided in section 2.8 of the
Credit Agreement. No Interest Period for a Bridge Loan which is a Eurodollar
Loan may be selected which would end after November 30, 2000.

          (e)  Once a Bridge Loan is incurred, it may not be prepaid except in
connection with a contemporaneous prepayment of all other Bridge loans and a
contemporaneous permanent reduction of the Total General Revolving Facility to
$160,000,000 or less, effected in accordance with the applicable provisions of
the Credit Agreement. Any Bridge Loan which is outstanding on the Temporary
Increase End Date shall be prepaid in full on the Temporary Increase End Date,
together with accrued interest and any breakage compensation payable pursuant to
section 2.10.

         1.2. INDEBTEDNESS COVENANT. Effective on the Effective Date of this
Amendment provided for in section 3 hereof, clause (c) of section 9.4 of the
Credit Agreement is amended to increase the amount specified therein, with the
result that such clause (c) as so amended will read in its entirety as follows:


<PAGE>

               (c)  Indebtedness incurred by Foreign Subsidiaries; PROVIDED that
          (i) the aggregate outstanding principal amount of such Indebtedness
          outstanding at any time shall not exceed the U.S. Dollar equivalent of
          Cdn$25,000,000, and (ii) at the time of any incurrence thereof after
          the date hereof, and after giving effect thereto, no Event of Default
          shall have occurred and be continuing or would result therefrom;

          1.3. CONSENT TO ACQUISITION; LIMITATION ON ACQUISITIONS. As
contemplated by the definition of "Permitted Acquisition" contained in section
1.1 of the Credit Agreement, the Lenders hereby consent to the Acquisition by
the Borrower of MidWest Audio Visual, Inc. and of Westek Presentation Systems,
Inc., on the terms generally described in the descriptive materials previously
furnished to the Lenders by the Borrower. Except as contemplated by the
preceding sentence, the Borrower will not directly or indirectly make any other
Acquisition during the period when Bridge Loans are available under the Credit
Agreement.

          1.4. AMENDMENT FEE. As consideration for the changes in the Credit
Agreement effected by sections 1.1 through 1.3 of this Amendment, the Borrower
will pay to the Administrative Agent, for PRO RATA distribution among the
Lenders in accordance with their respective General Revolving Commitments, an
amendment fee in the aggregate amount of $50,000, such amendment fee being
payable in immediately available funds on the date this Amendment becomes
effective as provided in section 3 hereof.

          2.   REPRESENTATIONS AND WARRANTIES.

          The Borrower represents and warrants to the Lenders and the
Administrative Agent as follows:

          2.1. AUTHORIZATION, VALIDITY AND BINDING EFFECT. This Amendment has
been duly authorized by all necessary corporate action on the part of the
Borrower, has been duly executed and delivered by a duly authorized officer or
officers of the Borrower, and constitutes the valid and binding agreement of the
Borrower, enforceable against the Borrower in accordance with its terms.

          2.2. REPRESENTATIONS AND WARRANTIES TRUE AND CORRECT. The
representations and warranties of the Borrower contained in the Credit
Agreement, as amended hereby, are true and correct on and as of the date hereof
as though made on and as of the date hereof, except to the extent that such
representations and warranties expressly relate to a specified date, in which
case such representations and warranties are hereby reaffirmed as true and
correct when made.

          2.3. NO EVENT OF DEFAULT, ETC. No condition or event has occurred or
exists which constitutes or which, after notice or lapse of time or both, would
constitute an Event of Default.

          2.4. COMPLIANCE. The Borrower is in full compliance with all covenants
and agreements contained in the Credit Agreement, as amended hereby.

          2.5. RECENT FINANCIAL STATEMENTS. The Borrower has furnished to the
Lenders and the Administrative Agent complete and correct copies of the
unaudited condensed consolidated balance sheet of the Borrower and its
consolidated subsidiaries as of June 30, 2000, and the related unaudited
condensed consolidated statements of income and of cash flows of the Borrower
and its consolidated subsidiaries for the fiscal period then ended. All such
financial statements have been prepared in accordance with GAAP, consistently
applied (except as stated therein), and fairly present the financial position of
the Borrower and its consolidated subsidiaries as of the date indicated and the
consolidated results of their operations and cash flows for the period
indicated.

          3.   EFFECTIVENESS.

          This Amendment shall become effective on a date (the "EFFECTIVE
DATE"), on or before September 27, 2000, if the following conditions are
satisfied on or before the Effective Date:

               (a)  this Amendment shall have been executed by the Borrower and
          the Administrative Agent, and counterparts hereof as so executed shall
          have been delivered to the Administrative Agent;

               (b)  the Acknowledgment and Consent appended hereto shall have
          been executed by the Credit Parties named therein, and counterparts
          hereof as so executed shall have been delivered to the Administrative
          Agent;



<PAGE>

               (c)  the Administrative Agent shall have been notified by all of
          the Lenders that such Lenders have executed this Amendment (which
          notification may be by facsimile or other written confirmation of such
          execution);

               (d)  the Borrower shall have duly executed and delivered to the
          Administrative Agent, for the account of the Lenders, additional
          General Revolving Notes made payable to the order of the respective
          Lenders in the amount of the temporary increase in their respective
          General Revolving Commitments provided for in this Amendment, and
          otherwise conforming to the requirements of the Credit Agreement;

               (e)  the Borrower shall have delivered to the Administrative
          Agent a certificate of its Secretary or an Assistant Secretary, dated
          as of a recent date, certifying the due adoption by the Board of
          Directors of a resolution or resolutions approving the increase in the
          Total General Revolving Commitment under the Credit Agreement to
          $170,000,000, and certifying that such resolution(s) remains in full
          force and effect, and such certificate and resolution(s) shall be
          satisfactory in form and substance to the Administrative Agent; and

               (f)  the Borrower shall have paid to the Administrative Agent,
          for the account of the Lenders, such amendment fees as are payable at
          such time as provided in section 1.4 of this Amendment (the
          Administrative Agent hereby agreeing to promptly re-transmit pro rata
          portions of the amendment fees to the respective Lenders).

Subject to satisfaction of the foregoing conditions, the Administrative Agent
shall notify the Borrower and each Lender in writing of the effectiveness
hereof.

          4.   RATIFICATIONS.

          The terms and provisions set forth in this Amendment shall modify and
supersede all inconsistent terms and provisions set forth in the Credit
Agreement, and except as expressly modified and superseded by this Amendment,
the terms and provisions of the Credit Agreement are ratified and confirmed and
shall continue in full force and effect.

          5.   MISCELLANEOUS.

          5.1. SUCCESSORS AND ASSIGNS. This Amendment shall be binding upon and
inure to the benefit of the Borrower, each Lender and the Administrative Agent
and their respective permitted successors and assigns.

          5.2. SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations
and warranties made in this Amendment shall survive the execution and delivery
of this Amendment, and no investigation by the Administrative Agent or any
Lender or any subsequent Loan or issuance of a Letter of Credit shall affect the
representations and warranties or the right of the Administrative Agent or any
Lender to rely upon them.

          5.3. REFERENCE TO CREDIT AGREEMENT. The Credit Agreement and any and
all other agreements, instruments or documentation now or hereafter executed and
delivered pursuant to the terms of the Credit Agreement as amended hereby, are
hereby amended so that any reference therein to the Credit Agreement shall mean
a reference to the Credit Agreement as amended hereby.

          5.4. EXPENSES. As provided in the Credit Agreement, but without
limiting any terms or provisions thereof, the Borrower agrees to pay on demand
all costs and expenses incurred by the Administrative Agent in connection with
the preparation, negotiation, and execution of this Amendment, including without
limitation the costs and fees of the Administrative Agent's special legal
counsel, regardless of whether this Amendment becomes effective in accordance
with the terms hereof, and all costs and expenses incurred by the Administrative
Agent or any Lender in connection with the enforcement or preservation of any
rights under the Credit Agreement, as amended hereby.

          5.5. SEVERABILITY. Any term or provision of this Amendment held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Amendment and the effect thereof shall be
confined to the term or provision so held to be invalid or unenforceable.



<PAGE>

          5.6. APPLICABLE LAW. This Amendment shall be governed by and construed
in accordance with the laws of the State of Ohio.

          5.7. HEADINGS. The headings, captions and arrangements used in this
Amendment are for convenience only and shall not affect the interpretation of
this Amendment.

          5.8. ENTIRE AGREEMENT. This Amendment is specifically limited to the
matters expressly set forth herein. This Amendment and all other instruments,
agreements and documentation executed and delivered in connection with this
Amendment embody the final, entire agreement among the parties hereto with
respect to the subject matter hereof and supersede any and all prior
commitments, agreements, representations and understandings, whether written or
oral, relating to the matters covered by this Amendment, and may not be
contradicted or varied by evidence of prior, contemporaneous or subsequent oral
agreements or discussions of the parties hereto. There are no oral agreements
among the parties hereto relating to the subject matter hereof or any other
subject matter relating to the Credit Agreement.

          5.9. COUNTERPARTS. This Amendment may be executed by the parties
hereto separately in one or more counterparts, each of which when so executed
shall be deemed to be an original, but all of which when taken together shall
constitute one and the same agreement.



<PAGE>


          IN WITNESS WHEREOF, this Amendment has been duly executed and
delivered as of the date first above written.

--------------------------------------------------------------------------------
MCSI,INC.,                                 PNC BANK, NATIONAL ASSOCIATION,
  A MARYLAND CORPORATION WHICH IS THE        INDIVIDUALLY AS A LENDER, A LETTER
  SUCCESSOR BY MERGER TO MIAMI COMPUTER      OF CREDIT ISSUER, THE SWING LINE
  SUPPLY CORPORATION, AN OHIO CORPORATION    LENDER AND AS ADMINISTRATIVE AGENT


                                           BY:_________________________________
BY:_________________________________            VICE PRESIDENT
     TITLE:
--------------------------------------------------------------------------------
NATIONAL CITY BANK,                        FIRSTAR BANK, N. A.
  INDIVIDUALLY AS A LENDER AND
  AS DOCUMENTATION AGENT

                                           BY:_________________________________
BY:_________________________________            TITLE:
     TITLE:
--------------------------------------------------------------------------------
KEY CORPORATE CAPITAL INC.                 THE HUNTINGTON NATIONAL BANK



BY:_________________________________       BY:_________________________________
     TITLE:                                     TITLE:
--------------------------------------------------------------------------------
BANK ONE, INDIANA, N. A.                   THE PROVIDENT BANK



BY:_________________________________       BY:_________________________________
     TITLE:                                     TITLE:
--------------------------------------------------------------------------------



<PAGE>


                           ACKNOWLEDGMENT AND CONSENT

          For the avoidance of doubt, and without limitation of the intent and
effect of sections 6 and 10 of the Amended and Restated Subsidiary Guaranty (as
such term is defined in the Credit Agreement referred to in the Amendment No. 10
to Amended and Restated Credit Agreement (the "AMENDMENT"), to which this
Acknowledgment and Consent is appended), each of the undersigned hereby
unconditionally and irrevocably (i) acknowledges receipt of a copy of the Credit
Agreement and the Amendment, and (ii) consents to all of the terms and
provisions of the Credit Agreement as amended by the Amendment.

          Capitalized terms which are used herein without definition shall have
the respective meanings ascribed thereto in the Credit Agreement referred to
herein. This Acknowledgment and Consent is for the benefit of the Lenders and
the Administrative Agent, any other person who is a third party beneficiary of
the Subsidiary Guaranty, and their respective successors and assigns. No term or
provision of this Acknowledgment and Consent may be modified or otherwise
changed without the prior written consent of the Administrative Agent, given as
provided in the Credit Agreement. This Acknowledgment and Consent shall be
binding upon the successors and assigns of each of the undersigned. This
Acknowledgment and Consent may be executed by any of the undersigned in separate
counterparts, each of which shall be an original and all of which together shall
constitute one and the same instrument.

          IN WITNESS WHEREOF, each of the undersigned has duly executed and
delivered this Acknowledgment and Consent as of the date of the Amendment
referred to herein.

--------------------------------------------------------------------------------
Diversified Data Products, Inc.                Electronic Image Systems, Inc.
Computer Showcase, Inc.                        Consolidated Media Systems, Inc.



By:_____________________________               By:_____________________________
   Michael E. Peppel, an officer                  Ira Stanley, an officer

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