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                            INDEMNIFICATION AGREEMENT


     This Agreement, dated as of January 28, 1998, is by and between STB
Systems, Inc., a Texas corporation (the "Company"), and Dennis G. Sabo
("Indemnitee").

                              W I T N E S S E T H :

     WHEREAS, the Company desires to have qualified directors serving on its
Board of Directors who are willing to make decisions that in their judgment are
in the Company's best interest without any undue threat of personal liability;

     WHEREAS, the Company's Amended and Restated Articles of Incorporation
("Articles of Incorporation") and the Company's Amended and Restated Bylaws
("Bylaws") require indemnification of each director or officer of the Company in
his capacity as a director or officer and, if serving at the request of the
Company as a director, officer, partner, venturer, proprietor, trustee,
employee, agent, or similar functionary of another foreign or domestic
corporation, partnership, joint venture, sole proprietorship, trust, employee
benefit plan, or other enterprise, in each of those capacities, against any and
all liability and reasonable expense that may be incurred by him in connection
with or resulting from (a) any threatened, pending, or completed action, suit,
or proceeding whether civil, criminal, administrative, arbitrative, or
investigative (collectively, a "Proceeding"), (b) an appeal in such a
Proceeding, or (c) any inquiry or investigation that could lead to such a
Proceeding, to the fullest extent permitted by the Texas Business Corporation
Act ("Act"), as the same exists or may be hereafter amended;

     WHEREAS, the Company desires to grant to Indemnitee the maximum
indemnification for any Loss (hereinafter defined) permitted by the Articles of
Incorporation and Bylaws;

     WHEREAS, developments with respect to the terms and availability of
directors' and officers' liability insurance and with respect to the
application, amendment, and enforcement of statutory, charter, and bylaw
indemnification provisions generally have raised questions concerning the
adequacy, and reliability of the protection afforded to persons intended to be
protected thereunder; and

     WHEREAS, in order to resolve such questions and thereby induce Indemnitee
to serve or to continue serving, as a director of the Company, the Company has
agreed to enter into this Agreement with Indemnitee;

     NOW, THEREFORE, in consideration of Indemnitee's consent to serve or
continuing to serve in the position of director of the Company, the parties
hereto agree as follows:

     1.   INDEMNITY OF INDEMNITEE.  The Company shall indemnify Indemnitee in 
his capacity as director, director nominee, and/or officer of the Company, as 
the case may be, and, if serving at the request of the Company as a director, 
director nominee, officer, trustee, employee, agent, or similar functionary 
of another foreign or domestic corporation, trust partnership, joint venture, 
sole proprietorship, employee benefit plan, or other enterprise, in each of 
those capacities, against any and all liability and reasonable expense that 
may be incurred by Indemnitee in connection with or resulting from (a) any 
Proceeding, (b) an appeal in such a 

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Proceeding, or (c) any inquiry or investigation that could lead to such a 
Proceeding, all to the fullest extent permitted by Article 2.02-1 of the Act. 
All indemnity obligations and/or liabilities of the Company hereunder shall 
be without limit and without regard to the cause or causes thereof or the 
negligence or gross negligence of any person or persons (expressly including 
Indemnitee), whether such negligence or gross negligence of Indemnitee be 
sole, joint or concurrent, active, or passive.

     2.   CONTINUATION OF INDEMNITY.  All agreements and obligations of the 
Company contained herein shall continue during the period Indemnitee is a 
director, director nominee or officer of the Company, shall be retroactive to 
the date Indemnitee first became a director, director nominee or officer 
covering all periods of service from time to time, and shall continue 
thereafter so long as Indemnitee shall be subject to any possible claim or 
threatened, pending, or completed Proceeding, any appeal in a Proceeding, and 
any inquiry or investigation that could lead to a Proceeding, by reason of 
the fact that Indemnitee was serving, or had consented to serve, in any 
capacity referred to herein.

     3.   NOTIFICATION AND DEFENSE OF CLAIM.  Promptly after receipt by 
Indemnitee of notice of any claim against Indemnitee or the commencement of 
any Proceeding, Indemnitee will, if a claim in respect thereof is to be made 
against the Company under this Agreement, notify the Company of the assertion 
of any such claim or the commencement thereof; but the omission so to notify 
the Company will not relieve it from any liability under this Agreement 
unless such delay in notification actually prejudiced the Company (and then 
only to the extent the Company was actually prejudiced thereby) and in 
addition, the Company shall not be relieved from any liability which it may 
have to Indemnitee otherwise than under this Agreement.  With respect to any 
such Proceeding as to which Indemnitee notifies the Company of the 
commencement thereof:

          (a)  The Company will be entitled to participate therein at its own
     expense.

          (b)  Except as otherwise provided below, to the extent that it may
     wish, the Company jointly with any other indemnifying party similarly
     notified will be entitled to assume the defense thereof with counsel
     satisfactory to Indemnitee, provided that, notwithstanding the Company's
     assumption of such defense, Indemnitee shall have the right to retain
     separate counsel and the Company shall pay all reasonable fees and expenses
     of such counsel and all other reasonable expenses of Indemnitee in
     connection with such Proceeding.  The Company shall not be entitled to
     assume the defense of any Proceeding brought by or on behalf of the Company
     or as to which Indemnitee shall have reasonably concluded that there may be
     a conflict of interest between the Company and Indemnitee in the conduct of
     the defense of such action.

          (c)  The Company shall not be liable to indemnify Indemnitee under
     this Agreement for any amounts paid in settlement of any action or claim
     effected without its written consent.  The Company shall not settle any
     action or claim in any manner which would impose any penalty or limitation
     on Indemnitee without Indemnitee's written consent.  Neither the Company
     nor Indemnitee will unreasonably withhold their consent to any proposed
     settlement.

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     4.   ADVANCES OF EXPENSES.  Reasonable expenses (other than judgments, 
penalties, fines and settlements) incurred by Indemnitee that are subject to 
indemnification under this Agreement (and not paid, reimbursed or advanced by 
others) shall be paid or  reimbursed by the Company in advance of the final 
disposition of the Proceeding within 30 days after the Company receives a 
written request by Indemnitee accompanied by substantiating documentation of 
such expenses, a written affirmation by Indemnitee of his good faith belief 
that he has met the standard of conduct necessary for indemnification under 
this Agreement, and a written undertaking by or on behalf of Indemnitee to 
repay the amount paid or reimbursed if it is ultimately determined that he 
has not met those standards or that such reasonable expenses do not 
constitute a Loss.  The written undertaking described above shall be an 
unlimited general obligation of Indemnitee and shall not be secured.  Such 
undertaking shall be without reference to the financial ability of Indemnitee 
to make repayment.

     5.   RIGHT OF INDEMNITEE TO INDEMNIFICATION UPON APPLICATION: PROCEDURE 
UPON APPLICATION.  Upon the written request of Indemnitee to be indemnified 
pursuant to this Agreement (other than pursuant to Section 4 hereof), the 
Company shall cause the Reviewing Party (hereinafter defined) to determine, 
within 45 days, whether or not the Indemnitee has met the relevant standards 
for indemnification required by this Agreement.  The termination of a 
Proceeding by judgment, order, settlement, or conviction, or on a plea of 
nolo contendere or its equivalent, shall not of itself create a presumption 
that Indemnitee did not meet the requirements for indemnification required by 
this Agreement.  If a determination of indemnification is to be made by 
Independent Legal Counsel (hereinafter defined), such Independent Legal 
Counsel shall render its written opinion to the Company and Indemnitee as to 
what extent Indemnitee will be permitted to be indemnified.  The Company 
shall pay the reasonable fees of Independent Legal Counsel and indemnify and 
hold harmless such Indemnitee against any and all expenses (including 
attorneys' fees), claims, liabilities and damages arising out of or relating 
to the engagement of Independent Legal Counsel pursuant hereto and the 
written opinion of such Independent Legal Counsel.

     6.   DEFINITIONS.  The terms defined in this Section 6 shall, for 
purposes of this Agreement have the indicated meanings:

          (a)  "Loss" shall mean any and all judgments, penalties (including
     excise and similar taxes), fines, settlements, and reasonable expense
     (including attorneys' fees) actually incurred by Indemnitee, after
     realization of or giving effect to all insurance, bonding, indemnification
     and other payments or recoveries actually received by or for the benefit of
     Indemnitee, directly or indirectly.

          (b)  "Reviewing Party" means, if a Change in Control (hereinafter
     defined) has not occurred (or if a Change in Control has occurred and such
     Change in Control has been approved by a majority of the Board of Directors
     of the Company who were directors of the Company immediately prior to such
     Change in Control), (i) a majority of a quorum of directors of the Company
     who at the time of voting upon a determination of indemnification are
     neither officers or employees of the Company or members of the immediate
     family of an officer or employee of the Company ("Interested Parties") nor
     parties to that particular Proceeding to which Indemnitee is seeking
     indemnification; or (ii) Independent Legal Counsel selected by a majority
     of a quorum of directors who at the 

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     time of selecting such Independent Legal Counsel are neither Interested 
     Parties nor parties to that particular Proceeding to which Indemnitee 
     is seeking indemnification, or if such a quorum cannot be obtained, by 
     a majority vote of a committee of the Board of Directors of the Company 
     designated to select such Independent Legal Counsel by a majority vote 
     of all directors of the Company, consisting solely of two or more 
     directors who at the time of such selection are neither Interested 
     Parties nor parties in that particular Proceeding to which Indemnitee 
     is seeking indemnification, or if such a quorum cannot be obtained and 
     such a committee cannot be established, by a majority vote of all 
     directors of the Company.  "Reviewing Party" means if a Change in 
     Control has occurred, Independent Legal Counsel selected in the manner 
     set forth in (ii) above.  

          (c)  "Change in Control" shall mean an event which shall be deemed to
     have occurred if:  (i) a merger or consolidation of the Company with or
     into another corporation occurs in which the Company shall not be the
     surviving corporation (for purposes of this definition, the Company shall
     not be deemed the surviving corporation in any such transaction if, as the
     result thereof, it becomes a wholly-owned subsidiary of another
     corporation); (ii) a dissolution of the Company occurs; (iii) a transfer of
     all or substantially all of the assets or shares of stock of the Company in
     one transaction or a series of related transactions to one or more other
     persons or entities occurs; (iv) if any "person" or "group" as those terms
     are used in Sections 13(d) and 14(d) of the Securities Exchange Act of
     1934, as amended (the "Exchange Act"), other than Excluded Persons, becomes
     the "beneficial owner" (as defined in Rule 13d-3 of the Exchange Act),
     directly or indirectly, of securities of the Company representing 50% or
     more of the combined voting power of the Company's then outstanding
     securities; or (v) during any period of two consecutive years commencing on
     or after April 1, 1995, individuals who at the beginning of the period
     constituted the Board cease for any reason to constitute at least a
     majority, unless the election of each director who was not a director at
     the beginning of the period has been approved in advance by directors
     representing at least two-thirds (2/3) of the directors then in office who
     were directors at the beginning of the period.  The term "Excluded Persons"
     means each of William E. Ogle, William D. Balthaser, Jr., and Mark S. Sims,
     and any person, entity, or group under the control of any of them, or a
     trustee or other fiduciary holding securities under an employee benefit
     plan of the Company.

          (d)  "Independent Legal Counsel" shall mean an attorney, selected in
     accordance with the provisions of Section 6(b) hereof, who shall not have
     otherwise performed services for Indemnitee, the Company, any person that
     controls the Company or any of the directors of the Company, within five
     years preceding the time of such selection (other than in connection with
     seeking indemnification under this Agreement).  Independent Legal Counsel
     shall not be any person who, under the applicable standards of professional
     conduct then prevailing, would have a conflict of interest in representing
     either the Company or Indemnitee in an action to determine Indemnitee's
     rights under this Agreement, nor shall Independent Legal Counsel be any
     person who has been sanctioned or censured for ethical violations of
     applicable standards of professional conduct.

     7.   ENFORCEABILITY.  The right to indemnification or advances as provided
by this Agreement shall be enforceable by Indemnitee in any court of competent
jurisdiction.  The burden of proof that indemnification is not appropriate shall
be on the Company.  Neither the 

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failure of the Company (including its Board of Directors or Independent Legal 
Counsel) to have made a determination prior to the commencement of such 
action that indemnification is proper in the circumstances because Indemnitee 
has met the applicable standard of conduct, nor an actual determination by 
the Company (including its Board of Directors or Independent Legal Counsel) 
that Indemnitee has not met such an applicable standard of conduct, shall be 
a defense to the action or create a presumption that Indemnitee has not met 
the applicable standard of conduct.

     8.   PARTIAL INDEMNITY; EXPENSES.  If the Indemnitee is entitled under 
any provision of this Agreement to indemnification by the Company for some or 
a portion of the expenses, judgments, fines, and penalties, but not for the 
total amount thereof, the Company shall indemnify Indemnitee for the portion 
thereof to which Indemnitee is entitled.  Notwithstanding any other provision 
of this Agreement, to the extent that Indemnitee has been successful on the 
merits or otherwise in defense of any or all Proceedings relating in whole or 
in part to an event subject to indemnification hereunder or in defense of any 
issue or matter therein, including dismissal without prejudice, Indemnitee 
shall be indemnified against expenses incurred for any Loss in connection 
with such Proceeding, issue or matter, as the case may be.

     9.   REPAYMENT OF EXPENSES.  Indemnitee shall reimburse the Company for 
all reasonable expenses paid by the Company in defending any Proceeding 
against Indemnitee in the event and only to the extent that it shall be 
ultimately determined that Indemnitee is not entitled to be indemnified by 
the Company for such expenses under the provisions of this Agreement.

     10.  CONSIDERATION.  The Company expressly confirms and agrees that it 
has entered into this Agreement and assumed the obligations imposed on the 
Company hereby in order to induce Indemnitee to consent to serve, to serve, 
and/or to continue serving as a director, and acknowledges that Indemnitee is 
relying upon this Agreement in consenting to serve and serving in such 
capacity.

     11.  INDEMNIFICATION HEREUNDER NOT EXCLUSIVE.  The indemnification and 
advancement of expenses provided by this Agreement shall not be deemed 
exclusive of any other rights to which Indemnitee may be entitled under any 
other agreement, vote of shareholders, as a matter of law, or otherwise. 

     12.  SUBROGATION.  If a payment is made under this Agreement, the 
Company shall be subrogated to the extent of such payment to all of the right 
of recovery of such Indemnitee, who shall execute all papers required and 
shall do everything that may be necessary to secure such rights.

     13.  SEVERABILITY.  Each of the provisions of this Agreement is a 
separate and distinct agreement and independent of the others, so that if any 
provision thereof shall be held to be invalid or unenforceable for any reason 
such invalidity or unenforceability shall not affect the validity or 
enforceability of the other provisions hereto.

     14.  NOTICE.  Any notice, consent, or other communication to be given 
under this Agreement by any party to any other party shall be in writing and 
shall be either (a) personally delivered, (b) mailed by registered or 
certified mail, postage prepaid with return receipt requested, (c) delivered 
by overnight express delivery service or same-day local courier service, or 
(d) 

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delivered by telex or facsimile transmission to the address set forth beneath 
the signature of the parties below, or at such other address as may be 
designated by the parties from time to time in accordance with this Section.  
Notices delivered personally, by overnight express delivery service, or by 
local courier service shall be deemed given as of actual receipt.  Mailed 
notices shall be deemed given three business days after mailing.  Notices 
delivered by telex or facsimile transmission shall be deemed upon receipt by 
the sender of the answerback (in the case of a telex) or transmission 
confirmation (in the case of a facsimile transmission).

     15.  GOVERNING LAW: BINDING EFFECT; AMENDMENT AND TERMINATION:
REIMBURSEMENT.

          (a)  This Agreement shall be interpreted and enforced in accordance
     with the laws of the State of Texas, without giving effect to Texas
     principles of conflicts of laws.

          (b)  This Agreement shall be binding upon Indemnitee and upon the
     Company, its successors, and assigns, and shall inure to the benefit of
     Indemnitee, his heirs, executors, administrators, personal representation,
     and assigns and to the benefit of the Company, its successors, and assigns.

          (c)  No amendment, modification, termination, or cancellation of this
     Agreement shall be effective unless in writing signed by both parties
     hereto.

          (d)  If Indemnitee is required to bring any action to enforce rights
     or to collect moneys due under this Agreement and is successful in such
     action, the Company shall reimburse Indemnitee for all of Indemnitee's
     reasonable fees and expenses in bringing and pursuing such action.




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     IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the
date first above written.

                              STB SYSTEMS, INC.



                              By:  /s/ William E. Ogle                    
                                   ---------------------------------------
                                   William E. Ogle, Chairman of the Board,
                                   President and Chief Executive Officer

                              Address of STB Systems, Inc.

                                   1651 North Glenville Drive, Suite 210
                                   Richardson, Texas 75085-0957
                                   Facsimile:  (214) 437-9631



                              /s/ Dennis G. Sabo                       
                              ---------------------------------------
                              Dennis G. Sabo, INDEMNITEE

                              Address of Indemnitee:

                              ---------------------------------------
                              ---------------------------------------
                              Facsimile:                             
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