LEASE SCHEDULE NO. 1000063905 dated as of December 15, 1997                LEASE
(New Equipment)

Master Lease Agreement dated October 30, 1996

Lessor:        Banc One Leasing Corporation

Lessee:        STB Systems, Inc.

1. GENERAL. This Lease Schedule is signed and delivered under the Master Lease
Agreement identified above, as amended from time to time ("Master Lease"),
between Lessee and Lessor. Capitalized terms defined in the Master Lease will
have the same meanings when used in this Schedule.

2. LEASE; EQUIPMENT DESCRIPTION. Lessor leases to Lessee, and Lessee leases from
Lessor, all of the property ("Equipment") described in SCHEDULE A-1 attached
hereto (and Lessee represents that all Equipment is new unless specifically
identified as used) on Schedule A-1.

3. LESSOR'S COST OF EQUIPMENT.


                                         
               Equipment Cost to Lessor:    $3,116,686.35
               Miscellaneous:               $0

               Lessor's Cost (total):       $3,116,686.35


4. LEASE TERM. The Lease Term of this Schedule shall be SIXTY (60) MONTHS and
shall commence on DECEMBER 15,1997 ("Commencement Date").

5. RENT.

                (a) As rent for the Equipment during the Lease Term, Lessee
        shall pay to Lessor MONTHLY rent with each such periodic rent payment
        being in the amount of $53,690.72. The first rent payment in the Lease
        Term shall be paid in ARREARS and all subsequent rent payments shall be
        paid on the same day of each MONTH thereafter.

                (b) There shall be added to each rent or other payment described
        in this Schedule all applicable Taxes as in effect from time to time.

6. FEES.

                (a) Lessee shall pay Lessor a Set-Up/Filing Fee of $375.00 which
        shall be due and payable on the Acceptance Date.

                (b) Security Deposit: $__ZERO__. On the Acceptance Date, Lessee
        shall pay Lessor said Security Deposit which shall be held In accordance
        with paragraph 11 below.



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7. TITLE TO EQUIPMENT; QUIET POSSESSION. Lessee agrees that Lessor is the lawful
owner of the Equipment and that good and marketable title to the Equipment shall
remain with Lessor at all times. Lessee at its sole expense will protect and
defend Lessor's good and marketable title to the Equipment against all claims
and demands whatsoever except for Liens created directly by Lessor. Lessee shall
have no right, title or interest in any of the Equipment except the right to
peacefully and quietly hold and use the Equipment in accordance with the terms
of the Lease during the Lease Term unless and until an event of default shall
occur.

8. LESSEE'S ASSURANCES. Lessee irrevocably and unconditionally: (a) reaffirms
all of the terms and conditions of the Master Lease and agrees that the Master
Lease remains in full force and effect; (b) agrees that the Equipment is and
will be used at all times solely for commercial purposes, and not for personal,
family or household purposes; and (c) incorporates all of the terms and
conditions of the Master Lease as if fully set forth in this Schedule.

9. CONDITIONS. No lease of Equipment under this Schedule shall be binding on
Lessor, and Lessor shall have no obligation to purchase the Equipment covered
hereby, unless: (a) Lessor has received evidence of all required insurance; (b)
in Lessor's sole judgment, there has been no material adverse change in the
financial condition or business of Lessee or any guarantor, (c) Lessee has
signed and delivered to Lessor this Schedule, which must be satisfactory to
Lessor, and Lessor has signed and accepted this Schedule; (d) no change in the
Code or any regulation thereunder, which in Lessor's sole judgment would
adversely affect the economics to Lessor of the lease transaction, shall have
occurred or shall appear to be imminent; (e) Lessor has received, in form and
substance satisfactory to Lessor, such other documents and information as Lessor
shall reasonably request (including, without limitation, Political Risk
Insurance described below in this Schedule); (f) STB DE MEXICO, S.A. DE C. V.
shall execute and deliver to Lessor a guaranty which must be satisfactory in
form and substance to Lessor (such satisfaction to be evidenced by Lessors
signature thereon); (g) the sublease or bailment of the Equipment described
below in this Schedule by Lessee as sublessor or bailor to STB DE MEXICO, S.A.
DE C. V. shall be executed and delivered to Lessor, and (h) Lessee has satisfied
all other reasonable conditions established by Lessor. Notwithstanding anything
to the contrary above in this paragraph, if Lessor executes and delivers the
Schedule to Lessee and if Lessor pays all of the suppliers of the Equipment the
full Lessor's Cost of the Equipment (the date as of which both of said events
shall have occurred will be called the "Funding Date"), then except as otherwise
specified in writing by Lessor to Lessee before said Funding Date, all
conditions to the Schedule being binding on Lessor will be deemed satisfied.

10. OTHER DOCUMENTS; EXPENSES. Lessee agrees to sign and deliver to Lessor any
additional documents deemed desirable by Lessor to effect the terms of the
Master Lease or this Schedule including, without limitation, Uniform Commercial
Code financing statements which Lessor is authorized to file with the
appropriate filing officers. Lessee hereby irrevocably appoints Lessor as
Lessee's attorney-in-fact with full power and authority in the place of Lessee
and in the name of Lessee to prepare, sign, amend, file or record any Uniform
Commercial Code financing statements or other documents deemed desirable by
Lessor to perfect, establish or give notice of Lessor's interests in the
Equipment or in any collateral as to which Lessee has granted Lessor a security
interest. Lessee shall pay upon Lessor's written request any actual
out-of-pocket costs and expenses paid or incurred by Lessor in connection with
the above terms of this section or the funding and closing of this Schedule.



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11. SECURITY DEPOSIT. As collateral for Lessee's obligations under the Lease,
Lessee hereby grants to Lessor a security interest in the sums specified in this
Schedule as a "Security Deposit." At its option, Lessor may apply all or any
part of said Security Deposit to cure any default of Lessee under the Lease. If
upon final termination of this Schedule, Lessee has fulfilled all of the terms
and conditions hereof, then Lessor shall pay to Lessee upon Lessee's written
request any remaining balance of the Security Deposit for this Schedule, without
interest.

12. REPRESENTATIONS AND WARRANTIES. Lessee represents and warrants that: (a)
Lessee is a corporation duly organized, validly existing and in good standing
under the laws of the state of its organization; (b) Lessee has full power,
authority and legal right to sign, deliver and perform the Master Lease, this
Schedule and all related documents and such actions have been duly authorized by
all necessary corporate action; and (c) the Master Lease, this Schedule and each
related document has been duly signed and delivered by Lessee and each such
document constitutes a legal, valid and binding obligation of Lessee enforceable
in accordance with its terms, except to the extent enforcement is limited by
State and Federal laws regarding bankruptcy, insolvency or debt reorganization
or other similar laws of general application or the application of principles of
equity.

13. SUBLEASE. Notwithstanding anything to the contrary in the Master Lease, with
respect to this Schedule, Lessor consents to the sublease or bailment of the
Equipment described in this Schedule by Lessee as sublessor or bailor to STB DE
MEXICO, S.A. DE C. V. as sublessee or bailee pursuant to the terms and
conditions of a Gratuitous Bailment Agreement and to the location of the
Equipment covered by the Schedule in the City of Ciudad Juarez, State of
Chihuahua, Mexico; provided, that the Gratuitous Bailment Agreement must be
satisfactory in form and substance to Lessor (such satisfaction to be evidenced
by Lessors signature thereon).

14. POLITICAL RISK INSURANCE. As used herein, "Political Risk Insurance" shall
mean a policy of insurance issued by National Union Fire Insurance Company of
Pittsburgh, PA ("Insurance Company") which insures Lessee and Lessor (or Lessors
assignee) against risks of expropriation or deprivation of the Equipment by the
government of the United Mexican States ("Political Loss") as set forth in such
policy of insurance. Lessee acknowledges that it has reviewed a copy of the
Political Risk Insurance policy.

                (a) With respect to this Schedule, Lessee shall be required to
        carry Political Risk Insurance as an additional requirement under
        Section 8 of the Master Lease and Lessee shall pay the premiums for the
        Political Risk Insurance that Lessor requires hereunder.

                (b) If a Political Loss occurs, such event shall be deemed a
        Casualty Loss under Section 9 of the Master Lease; provided, that (1)
        Lessee agrees to continue to pay rent and perform its other obligations
        under this Schedule and the Master Lease until the earlier of the date
        that the Insurance Company pays the amounts due under the Political Risk
        Insurance or the date that Lessor has exhausted its rights and remedies
        under the Political Risk Insurance; (2) Lessor agrees that it will
        pursue with reasonable diligence its rights against the Insurance
        Company under the Political Risk Insurance; and (3) notwithstanding
        anything to the contrary in Section 9 of the Master Lease as it relates
        to this Schedule, within thirty (30) days of the earlier of the date
        that the Insurance



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        Company pays the amounts due under the Political Risk Insurance or the
        date that Lessor has exhausted its rights and remedies under the
        Political Risk Insurance, Lessee shall pay to Lessor the Stipulated Loss
        Value of the Equipment affected by the Political Loss less the aggregate
        of the amount that the Insurance Company has paid to Lessor under the
        Political Risk Insurance and the amount that the United Mexican States
        has paid to Lessor as a result of the Political Loss plus the reasonable
        expenses incurred by Lessor to collect such amounts from the Insurance
        Company and the United Mexican States.

15. CANCELLATION OPTION. So long as no event of default has occurred and
continues under the Master Lease or any Schedule thereto and so long as Lessee
gives Lessor written notice of its election under this paragraph at least 90
days, but no more than 180 days, prior to the Cancellation Date (as defined
below), Lessee may, subject the provisions of this paragraph, elect to cancel
this Schedule and return all of the Equipment. Lessee may not cancel the
Schedule under the terms of this paragraph unless and until all of the following
conditions have been satisfied in full on or before the Cancellation Date:

                (a) Lessee shall pay to Lessor on the applicable Cancellation
        Date a return and remarketing fee equal to the Cancellation Value (as
        defined below); AND

                (b) Lessee shall return all, but not less than all, of the
        Equipment to Lessor on the Cancellation Date in full compliance with
        subsection 23(b) of the Master Lease and with all other return and
        maintenance requirements of this Schedule.

"Cancellation Value" means the total of the following: (i) all rent, Taxes and
all other amounts then due and payable by Lessee under this Schedule and Master
Lease to the extent it relates to this Schedule; plus (ii) an amount equal to
SIXTY-ONE PERCENT (61%) of the Lessor's Cost of the Equipment stated above in
this Schedule; plus (iii) sales and other Taxes due in connection with Lessor's
receipt of the above amounts. "Cancellation Date" means the scheduled rent
payment date in the 24TH MONTH OF THE LEASE TERM.

16. AMENDMENT OF PURCHASE OPTION AND RETURN OPTION.

                (a) Solely for purposes of this Schedule and its Equipment,
        Lessor and Lessee agree that if Lessee elects to exercise its option to
        purchase the Equipment at the end of the Lease Term (which option is
        described in Section 23(c) of the Master Lease), then, notwithstanding
        anything to the contrary in this Schedule or the Master Lease, the
        provisions of Section 23(d) of the Master Lease for determining Fair
        Market Value for purposes of this purchase option shall not apply and
        the purchase price of the Equipment at the end of the Lease Term shall
        be equal to the Fixed Price stated below plus all Taxes (excluding
        income taxes on Lessor's gains on such sale), costs and expenses
        incurred or paid by Lessor in connection with such sale plus all accrued
        and unpaid amounts then due and payable with respect to the Equipment or
        this Schedule.

                Fixed Price:  twenty-five percent (25%) of the above Lessor's
                              Cost of the Equipment

                (b) Solely for purposes of this Schedule and its Equipment,
        Lessor and Lessee agree that if Lessee elects to exercise its option to
        return the Equipment at the end of the



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        Lease Term (which option is described in Section 23(b) of the Master
        Lease), then Lessee shall return the Equipment in full compliance with
        Section 23(b) of the Master Lease and with all other return and
        maintenance requirements of this Schedule and there shall be a rent
        adjustment as provided below in this subparagraph (b). The scheduled
        expiration date of the Lease Term specified in this Schedule will be
        referred to as the "Termination Date".

                (1)     If the Actual Sale Proceeds as determined pursuant to
                        subparagraph (c) of this paragraph are less than the
                        Fixed Price, then (A) Lessor shall retain the Actual
                        Sale Proceeds and (B) Lessee shall pay to Lessor the
                        difference between the Fixed Price and such Actual Sale
                        Proceeds on the Termination Date, provided, that the
                        amount of said deficiency payable by Lessee to Lessor
                        shall not exceed TWENTY-FOUR PERCENT (24%) of the above
                        Lessor's Cost of the Equipment; or

                (2)     If the Actual Sale Proceeds as determined pursuant to
                        subparagraph (c) of this paragraph equal or exceed the
                        Fixed Price, then Lessor shall retain the entire Actual
                        Sale Proceeds.

                (3)     In all events, Lessee shall pay all Taxes (excluding
                        income taxes on Lessor's gains on such sale), costs and
                        expenses incurred or paid by Lessor in connection with
                        any such sale plus all accrued and unpaid amounts due
                        and payable with respect to the Equipment or this
                        Schedule up to the date of any such sale.

                (4)     If for any reason whatsoever Lessee fails to return the
                        Equipment in full compliance with Section 23(b) of the
                        Master Lease and with all other return and maintenance
                        requirements of this Schedule on or before the
                        Termination Date, then Lessee shall be deemed to have
                        elected to purchase Equipment pursuant to subparagraph
                        (a) of this paragraph.

Unless otherwise expressly agreed by Lessor in writing, during the 90-day period
prior to the Termination Date, Lessee shall, and Lessor may, solicit offers to
purchase the Equipment from prospective purchasers. Neither Lessee nor third
parties affiliated with the Lessee may bid to purchase the Equipment. Lessor may
bid to purchase the Equipment.

                (c) if one or more such offers to purchase the Equipment are
        received under subparagraph (b) of this paragraph, then the Equipment
        shall be sold by Lessor to the highest bidder within ten (10) days after
        the Termination Date and the Actual Sale Proceeds shall equal the
        purchase price actually received by Lessor after deducting all
        reasonable selling expenses. If no such offers to purchase the Equipment
        are received or if the Equipment is not sold for any reason, then the
        Actual Sale Proceeds shall be deemed to be zero and Lessee shall pay the
        Fixed Price to Lessor pursuant to clause (1) of subparagraph (b) of this
        paragraph plus all accrued and unpaid amounts due and payable with
        respect to the Equipment or this Schedule up to the date of any such
        payment. If Lessor subsequently sells the Equipment, then the purchase
        price actually received by Lessor, after deducting all reasonable
        selling expenses, shall be distributed as



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        follows: first, to Lessor in an amount equal to the Fixed Price less the
        payment made by Lessee pursuant to clause (1) of subparagraph (b) of
        this paragraph; second, to Lessee, to the extent of its payment to
        Lessor pursuant to clause (1) of subparagraph (b) of this paragraph; and
        lastly, the remainder to Lessor.

                (d) Lessor shall, upon receipt of the purchase price of the
        Equipment under this paragraph, convey title to the Equipment to the
        purchaser by a bill of sale, which transfer shall be "AS-IS, WHERE IS,"
        with all faults, without recourse to Lessor and without any
        representation or warranty of any kind whatsoever by Lessor, express or
        implied.

17. TAX BENEFIT. Solely for purposes of this Schedule and its Equipment, it is
the intention of the parties that Lessor shall not be entitled to such
deductions, credits and other tax benefits as are provided by federal, state,
and local income tax law to an owner of the Equipment and Section 10 of the
Master Lease is deleted. NOTWITHSTANDING ANYTHING TO THE CONTRARY IN THE MASTER
LEASE OR THIS SCHEDULE, LESSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS
OR IMPLIED, AS TO THE TAX OR ACCOUNTING TREATMENT OR CONSEQUENCES OF THIS
SCHEDULE OR THE TRANSACTIONS CONTEMPLATED HEREBY.

18. GOVERNING DOCUMENT. In the event of any conflict between the terms of the
Master Lease and the terms of this Schedule as each is amended by its addenda,
the terms of this Schedule shall control.

19. SAVINGS CLAUSES. (a) If any court or other judicial authority determines
that this Schedule is a loan transaction or a conditional sale transaction, then
Lessor and Lessee agree: (1) that the original principal amount financed
pursuant to this Schedule is the Lessor's Cost set forth in paragraph 3 of this
Schedule; and (2) that Lessee shall pay said principal amount, together with
interest at the per annum rate of 8.62%, by paying all rentals and other amounts
due under the Schedule plus the Fixed Price set forth in paragraph 16 of this
Schedule.

        (b) If any court or other judicial authority determines that this
Schedule is a loan transaction or a conditional sale transaction, then as
collateral security for payment and performance of all Secured Obligations
(defined below) and to induce Lessor to extend credit from time to time to
Lessee (under the Master Lease or otherwise), Lessee hereby grants to Lessor a
first priority security Interest in all of. Lessee's right, title and Interest
In the Equipment, whether now existing or hereafter acquired, and in all
Proceeds (defined below), and Lessee, at its sole expense, will protect and
defend Lessor's first priority security interest in the Equipment against all
claims and demands whatsoever. Lessee agrees that Lessor shall have all rights
of a secured party under the applicable Uniform Commercial Code. "Secured
Obligations" means (1) all payments and other obligations of Lessee under or in
connection with this Schedule, and (2) all payments' and other obligations of
Lessee (whether now existing or hereafter incurred) under or in connection with
the Master Lease and all present and future Lease Schedules thereto, and (3) all
other leases, indebtedness, liabilities and/or obligations of any kind (whether
now existing or hereafter incurred, absolute or contingent, direct or indirect)
of Lessee to Lessor or to any affiliate of either Lessor or BANC ONE
CORPORATION. "Proceeds" means all cash and



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non-cash proceeds of the Equipment including, without limitation, proceeds of
insurance, indemnities and/or warranties.

20. PURCHASE-ORDERS AND ACCEPTANCE OF EQUIPMENT. Lessee agrees that (i) Lessor
has not selected, manufactured, sold or supplied any of the Equipment, (ii)
Lessee has selected all of the Equipment and its suppliers, and (iii) Lessee has
received a copy of, and approved, the purchase orders or purchase contracts for
the Equipment. AS BETWEEN LESSEE AND LESSOR, LESSEE AGREES THAT: (a) LESSEE HAS
RECEIVED, INSPECTED AND APPROVED ALL OF THE EQUIPMENT; (b) ALL EQUIPMENT IS IN
GOOD WORKING ORDER AND COMPLIES WITH ALL PURCHASE ORDERS OR CONTRACTS AND ALL
APPLICABLE SPECIFICATIONS; (c) LESSEE IRREVOCABLY ACCEPTS ALL EQUIPMENT FOR
PURPOSES OF THE LEASE "AS-IS, WHERE-IS" WITH ALL FAULTS; AND (d) LESSEE
UNCONDITIONALLY WAIVES ANY RIGHT THAT IT MAY HAVE TO REVOKE ITS ACCEPTANCE OF
THE EQUIPMENT.

LESSEE HAS READ AND UNDERSTOOD ALL OF THE TERMS OF THIS SCHEDULE. LESSEE AGREES
THAT THERE ARE NO ORAL OR UNWRITTEN AGREEMENTS WITH LESSOR REGARDING THE
EQUIPMENT OR THIS SCHEDULE.

Banc One Leasing Corporation           STS Systems, Inc.
(Lessor)                               (Lessee)


By:  /s/ Anthony Park                  By:  /s/ Jim Hopkins
   ----------------------------------     --------------------------------------

Title: Funding Authority               Title: Vice President
      --------------------------------       -----------------------------------


Lessor's Acceptance Date:  December ___, 1997



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Source: OneCLE Business Contracts.