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                                                                   EXHIBIT 10.21

               [NUMBER NINE VISUAL TECHNOLOGY LOGO APPEARS HERE]




                                            November 20, 1997


Ms. Beverly Schultz:
--------------------

     RE:  SEPARATION LETTER AGREEMENT
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Dear Beverly:

     The purpose of this letter is to confirm the terms regarding your 
separation of employment with the Number Nine Visual Technology Corporation (the
"Company" or  "Number Nine").  As more fully set forth below, the Company 
desires to provide you with severance pay and benefits and exchange for certain 
agreements by you.


     1.   SEPARATION OF EMPLOYMENT.  Your employment with the Company will 
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terminate effective October 24, 1997 (the "Separation Date").  You acknowledge 
that from and after the Separation Date, you shall have no authority and shall 
not represent yourself as an employee or agent of the Company.  

     2.   SEVERANCE PAY AND BENEFITS.  In exchange for the mutual covenants set 
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forth in this letter, and commencing on the eighth day following your execution 
of this Letter Agreement (the "Effective Date"), the Company agrees to provide 
you with the following Severance Pay and Benefits.

     (i)   Continue to provide sick pay until the end of your approved family
           leave (November 17, 1997) in the gross amount of Eight Thousand One
           Hundred and Fifty Three Dollars and Eighty Six Cents ($8,153.86) less
           applicable taxes.
     (ii)  Severance Pay in the gross amount of Sixteen Thousand Three Hundred
           and Seven Dollars and Twenty cents ($16,307.20), less applicable
           taxes, which sum represents pay through December 31, 1997, and shall
           be paid to you in one lump sum payable on the eighth day following
           your execution of this Letter Agreement.
     (iii) Continuation of your participation in Number Nine's medical and
           dental insurance programs to the same extent that such insurance is
           provided to persons still employed by Number Nine until December 31,
           1997. You shall have the right to continue your medical and dental
           insurance programs to the same extent that such insurance is provided
           to persons still employed by Number Nine until December 31, 1997. You
           shall have the right to continue your medical and dental insurance
           after that time, at your sole expense, pursuant to the provisions of
           the Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA");
           provided, however, that you timely elect COBRA. The COBRA period
           shall be deemed to have commenced on October 24, 1997.
     (iv)  You may take ownership of (at not cost to you) the Twinhead laptop
           computer and docking station which was issued to you by the Company
           value $4,100.

     You acknowledge and agree that the Severance Pay and Benefits provided
herein are

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not otherwise due or owing to you under any Company employment agreement (oral 
or written) or Company policy or practice, nor is this Severance Pay and 
Benefits intended to, and shall not, constitute a severance plan, and shall 
confer no benefit on anyone other than the parties hereto.  You further 
acknowledge that except for (i) the specific financial consideration set forth 
in this letter, and (ii) any accrued vacation days that are earned as of the 
Separation Date, which the Company paid on the Separation Date, you have been 
paid and provided all wages, commissions, bonuses, vacation pay, holiday pay and
any other form of compensation or benefit that may be due to you now or which 
would have become due in future in connection with your employment with or 
separation of employment from Number Nine.  

     3.   STOCK RIGHTS.  To the extent applicable, all of the terms, rights and 
          -------------
conditions of the (a) Number Nine Computer Corporation 1989 Stock Option Plan,
and (b) the Number Nine Computer Corporation 1994 Employee, Director and
Consultant Plan (jointly the "Stock Option Plans"), and any documents executed
by you pursuant to the issuance of any stock options under the Stock Option
Plans, are hereby incorporated by reference and shall survive the signing of
this Agreement. You will be allowed to immediately exercise and sell any and all
of your stock options which have vested (12,500 options) since the date of grant
(May 28, 1996) at a purchase price of $3.07 per share. In addition, the economy
will accelerate the vesting of 12,500 additional options. Normally you would not
be eligible to exercise and sell these options until mid February 1998. The
value of these 25,000 options on October 28, 1997 was $26,374 (this value will
change based on stock market variations). Except for the foregoing if
applicable, you acknowledge and agree that you do not have now, and shall not in
the future have, any rights in, including any rights to vest in, any stock
options under any Number Nine stock or stock option plan (of whatever name or
kind) that you may have participated in or were eligible to participate in
during your employment.

     4.   CONFIDENTIALITY/NON-COMPETITION/NON-SOLICITATION: You hereby and 
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ackowledge the following:

     (i)   that you have returned to Number Nine all Number Nine documents (and
     any copies thereof) and property, that you shall abide by the provisions of
     the "Non-Compete and Confidentiality Agreement" previously executed by you
     and attached hereto as Exhibit A (the terms of which are hereby
     incorporated by reference and shall survive the signing of this Agreement),
     and that you otherwise shall abide by any and all common low and/or
     statutory obligations relating to protection and non-disclosure of Number
     Nine's trade secrets and/or confidential and proprietary documents and
     information; however, notwithstanding the foregoing, you shall not be
     deemed to be in violation of section 2 or your Non-Compete and
     Confidentiality Agreement so long as such employment or association does
     not involve development, manufacture, sale or distribution of products
     directly competitive with the products developed, manufactured, sold or
     distributed by Number Nine.

     
     (ii)  that all information relating in any way to the subject matter if 
this Letter

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     Agreement, including the terms and amounts, shall be held confidential by
     you and shall not be publicized or disclosed to any person (other than an
     immediate family member, legal counsel or financial advisor, provided that
     any such individual to whom disclosure is made agrees to be bound by these
     confidentiality obligations), business entity or government agency (except
     as mandated by state of federal law).

     (iii) That you will not make any statements that are professionally or
     personally disparaging about, or adverse to, the interests of Number Nine
     (including its officers, directors and employees) including, but not
     limited to, any statements that disparage any person, product, service,
     finances, financial condition, capability or any other aspect of the
     business of Number Nine, or engage in any conduct which is intended to harm
     professionally or personally the reputation of Number Nine (including its
     officer, directors and employees);

     (iv) that the breach of any of the foregoing covenants by you shall
     constitute a material breach of this Agreement and shall relieve Number
     Nine of any further obligations hereunder and, in addition to any other
     legal or equitable remedy available to Number Nine, shall entitle Number
     Nine to recover any monies already paid to you pursuant to Section 2 of
     this Letter Agreement.

     5.    RELEASE OF CLAIMS: You hereby agree and acknowledge that by signing
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this letter and accepting the Severance Pay and Benefits discussed in Section 2
to be provided to you, and other good and valuable consideration provided for in
this letter, you are waiving your right to assert any form of legal claim
against Number Nine, its divisions, affiliates, subsidiaries and related
entities, and its and their respective officers, directors, employees, agents,
successors and assigns) of any kind whatsoever from the beginning of time
through the Effective Date of this Letter Agreement. Your waiver and release
herein is intended to bar any form of legal claim, charge, complaint or any
other form of action (jointly referred to as "Claims") against the Company
seeking any form of relief including, without limitation, equitable relief
(whether declaratory, injunctive or otherwise), the recovery of any damages or
any other form of monetary recovery whatsoever (including, without limitation,
back pay, front pay, compensatory damages, emotional distress damages, punitive
damages, attorneys fees and any other costs) against the Company, up through
the Effective Date.

      Without limiting the foregoing general waiver and releasem you 
specifically waive and release the Company from any Claim arising from or 
related to your employment relationship with the Company or the termination 
thereof, including, without limitation:

     **    Claims under any state or federal discrimination, fair employment
           practices or other employment related statute, regulation or
           executive order(as they may have been amended through the Effective
           Date) prohibiting discrimination or harassment based upon any
           protected status including, without limitation, race, national
           origin, age, gender, marital status, disability, veteran status or
           sexual orientation. Without limitation, specifically included in this
           paragraph are any


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           Claims arising under the federal Age Discrimination in Employment
           Act, the Older Workers Benefit Protection Act, the Civil Rights Acts
           of 1966 and 1971, Title VII of the Civil Rights Act of 1964, the
           Civil Rights Act of 1991, the Equal Pay Act, the Americans With
           Disabilities Act and any similar Massachusetts or other state
           statute.
           
     **    Claims under any other state or federal employment related statute,
           regulation or executive order (as they may have been amended through
           the Effective Date) relating to wages, hours or any other terms and
           conditions of employment. Without limitation, specifically included
           in this paragraph are any Claims arising under the Fair Labor
           Standards Act, the Family and Medical Leave Act of 1993, the National
           Labor Relations Act, the Employee retirement Income Security Act of
           1974, the Consolidated Omnibus Budget Reconciliation Act of 1985
           (COBRA) and any similar Massachusetts or other state statute.

     **    Claims under any state or federal common law theory including,
           without limitation, wrongful discharge, breach of express or implied
           contract, promissory estoppel, unjust enrighment, breach of a
           covenant of good faith and fair dealing, violation of public policy,
           defamation, interference with contractual relations, intentional or
           negligent infliction of emotional distress, invasion of privacy,
           misrepresentation, deceit, fraud or negligence.

     **    Any other Claim arising under state or federal law.

     Nothwithstanding the foregoing, this Section shall not release the Company
from any obligation expressly set forth in this Letter Agreement. You
acknowledge and agree that, but for providing this release of claims, you would
not be receiving the Severance Pay and Benefits being provided to you under the
terms of this Letter Agreement.

     Number Nine and you hereby acknowledge that because you are over 40 
years of age, you are granted specific rights under the Older Workers Benefit 
Protection Act ("OWBPA"), which prohibits discrimination on the basis of age, 
and the release set forth in this section is intended to release any right that 
you may have to file a claim against Number Nine alleging discrimination on the 
basis of age.  Consistent with the provisions of OWBPA, Number Nine is providing
you with forty-five (45) days in wich to consider and accept the terms of this 
Letter Agreement by signing below.  In addition, you may rescind your assent to 
this Letter Agreement if, within seven (7) days after the date you sign this 
Letter, you deliver a notice of recision to Michael Albanese at Number Nine.  To
be effective, such recision must be hand delivered or postmarked within the 
seven (7) day period and sent by certified mail, return receipt requested, to 
Michael Albanese, Human Resources, Number Nine Visual Technology Corporation at 
18 Hartwell Avenue, Lexington, MA 02173.



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     6.   ENTIRE AGREEMENT/CHOICE OF LAW/FULL AGREEMENT.  This Letter Agreement 
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supersedes any and all prior oral and/or written agreements, and sets forth the
entire agreement between you and the Company. No variations or modifications
hereof shall be deemed valid unless reduced to writing and signed by the parties
hereto. This Letter Agreement shall take effect as an instrument under seal and
shall be governed by and construed in accordance with the laws of the
Commonwealth of Massachusetts. The provisions of this Letter of Agreement are
severable, and if for any reason any part hereof shall be found to be
unenforceable, the remaining provisions shall be enforced in full.

     It is the Company's desire and intent to make certain that you fully 
understand the provisions and effects of this letter.  To that end, you have 
been encouraged and given the opportunity to consult with legal counsel for the 
purpose of reviewing the terms of this letter.  Also, by executing this letter, 
you are acknowledging that you have been afforded sufficient time to understand
the terms and effects of this letter, that your agreements and obligations 
hereunder are made voluntarily, knowingly and without duress, and that neither 
the Company nor its agents or representatives have made any representations 
inconsistent with the provisions of this letter.

     If the foregoing correctly sets forth our understanding, please sign, date 
and return the enclosed copy of this letter to Michael Albanese at the Company 
within the time frame discussed in this letter.

                                            Very truly yours,


                                            Number Nine Visual Technology Corp.

                                        By: /s/ Michael Albanese
                                            -----------------------------
                                            Michael Albanese

Confirmed and Agreed:


/s/ Beverly Schultz
----------------------------
Beverly Schultz
Dated: November 20, 1997

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