ADDENDUM TO BUSINESS LOAN AGREEMENT

THIS ADDENDUM TO BUSINESS LOAN AGREEMENT  ("Addendum")  is made and entered into
effective as of the 5th day of February  1999, by and between U.S. BANK NATIONAL
ASSOCIATION   ("Lender"),   and  EVANS  AND  SUTHERLAND   COMPUTER   CORPORATION
("Borrower").

                                    RECITALS:
A. Lender and Borrower  entered into a Business Loan  Agreement,  dated November
13, 1998 (the "Loan  Agreement")  pursuant to which Lender  agreed to advance to
Borrower an  unsecured  revolving  line of credit in the maximum  line amount of
$20,000,000.00  (the  "Loan").  B. Lender and Borrower  desire to amend  certain
provisions of the Loan Agreement and to make corresponding  changes to the other
documents  evidencing  Borrower's  obligations  to Lender under the Loan, as set
forth below in this Addendum.  NOW,  THEREFORE,  in  consideration of the mutual
promises   contained  in  this  Addendum,   and  for  other  good  and  valuable
consideration.   the  receipt  and  legal   sufficiency   of  which  are  hereby
acknowledged,  Lender and Borrower agree as follows: 

1. Loan Documents. As used in this Addendum, the term "Loan Documents" refers to
the  following  documents,  dated  effective as of November 13, 1998,  signed by
Borrower relating to the Loan:

     (a) The Loan Agreement;  
     (b) The Alternative  Rate Options  Promissory Note (Prime Rate, LIBOR), in 
     the maximum principal amount of $20,000,000.00; 
     (c) The Negative Pledge  Agreement (the "Negative Pledge  Agreement");  
     (d) The Corporate Resolution to Borrow; and (e) The Loan Checklist.

2.  Definition of Borrower.  The definition of the term  "Borrower" set forth in
the Loan Agreement is deleted in its entirety and replaced by the following:

         Borrower.  The word  "Borrower"  means  EVANS AND  SUTHERLAND  COMPUTER
CORPORATION.  The foregoing definition shall amend all references to Borrower in
all of the Loan Documents. 

3. Actions by Lender. In the Loan Documents,  whenever Lender is granted a right
to take action against Borrower as a result of a default, act, or omission by or
on the part of  Borrower,  or to otherwise  exercise its judgment or  discretion
under the Loan  Documents,  unless  Lender,  under the express terms of the Loan
Documents,  is  required to act under a higher  standard of care,  such as "good
faith," Lender shall be required to act reasonably.

4.  Materiality.  In the event Borrower does not satisfy the requirements of any
affirmative or negative covenant  contained in any of the Loan Documents,  or in
the event a  representation  or  warranty  given by  Borrower in any of the Loan
Documents  proves to be or to have been incorrect when made,  such  circumstance
shall not be deemed an event of default under the Loan Documents: (a) so long as
there is no  outstanding  balance  under the Note;  or (b) if there is a balance
under the Note (1) so long as Borrower is in  compliance  with all covenants and
financial  ratios  contained in the Loan  Agreement both before and after giving
effect to such  circumstance,  or (2)  unless  the same  results  in a  material
impairment of Borrower's ability to repay the Loan, or would disqualify Borrower
From  receiving  credit from Lender based on Lender's then current  underwriting
standards.  Nothing  contained in this paragraph shall be deemed a waiver of any
condition  precedent  to an advance of Loan  proceeds as  described  in the Loan
Agreement.

5. Grace  Period.  Upon the  occurrence  of an event of default under any of the
Loan Documents, Lender shall give Borrower notice and an opportunity to cure the
default in accordance with the following:

         (a)  Monetary  Default.  Borrower  shall not be  entitled to any notice
         regarding  defaults  with  respect to regularly  scheduled  payments of
         principal and accrued interest under the Note. However, in the event of
         any other  monetary  default,  Borrower  shall  have 15 days  following
         receipt of written  notice from  Lender in which to cure such  default.

         (b)  Nonmonetary  Default.  In  the  event  of a  nonmonetary  default,
         Borrower shall have 30 days after receipt of written notice from Lender
         specifying the nonmonetary  default in which to effect a cure. However,
         if the nonmonetary  default cannot  reasonably be corrected within such
         30-day period, Borrower shall have an additional 30 days to remedy such
         nonmonetary  default if Borrower notifies Lender of the manner in which
         the nonmonetary  default shall be cured, and if appropriate  corrective
         action  is  instituted   within  the  original  30-day  period  and  is
         diligently pursued thereafter.

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Occurrence  of an event of  default  under any of the Loan  Documents  shall not
entitle  Lender to exercise its rights and remedies  under the Loan Documents or
applicable law, unless such event is not cured within the applicable  notice and
cure period.  

6. Financial  Covenants and Ratios.  Unless otherwise  expressly  defined in the
Loan  Agreement,  all  financial  covenants  and  ratios  described  in the Loan
Agreement shall be calculated using Borrower's consolidated financial statements
and the  definitions  and  standards  imposed by generally  accepted  accounting
principles.  Borrower's  financial reporting  requirements shall be satisfied by
Borrower  submitting  consolidated  financial  statements and information as set
forth in the Loan Agreement.

7. Cash Flow Requirements.  The cash flow requirements covenant contained in the
"Affirmative Covenants" section of the Loan Agreement is deleted in its entirety
and replaced by the following:

         Cash  Flow  Requirements.  Maintain  Cash  Flow at not  less  than  the
         following  level:  Debt Service Coverage (DSC) ratio of greater than or
         equal  to 3.50 to  1.00.  DSC  ratio  is  defined  as  earnings  before
         interest,  taxes,  depreciation,  amortization,  and all other  noncash
         expenses  divided by current portion  long-term debt plus interest plus
         dividends.  DSC ratio  will be  calculated  on a  rolling  four-quarter
         basis.  Additionally,  for  calculation of this ratio,  the $27,925,000
         loss from the  write-off of  capitalized  R&D expenses will be excluded
         through September of 1999.

8. Indebtedness and Liens. The negative covenant in the Loan Agreement regarding
"Indebtedness  and  Liens"  is  deleted  in its  entirety  and  replaced  by the
following:

         Indebtedness  and Liens.  (a) Except for trade debts and capital leases
         incurred  or  entered  into  in  the  normal  course  of  business  and
         indebtedness to Lender contemplated by this Agreement, create, incur or
         assume  indebtedness  for  borrowed  money,  (b) except as allowed as a
         Permitted  Lien or  otherwise  accomplished  in the  normal  course  of
         business,  sell,  transfer,  mortgage,  assign,  pledge,  lease grant a
         security interest in, or encumber any of Borrower's assets, or (c) sell
         with recourse any of Borrower's accounts, except to Lender.

9. Net Worth Ratio.  The net worth ratio covenant  contained in the  "Additional
Financial  Covenants and Ratios" section of the Loan Agreement is deleted in its
entirety and replaced by the following:

         Net Worth Ratio.  Maintain a ratio of Total Liabilities to Tangible Net
         Worth of less than .65 to 1.00.  Net Worth  Ratio is  defined  as total
         liabilities minus  subordinated debt divided by tangible net worth plus
         subordinated debt.

10. Subsidiaries and Affiliates of Borrower. The miscellaneous  provision in the
Loan Agreement regarding "Subsidiaries and Affiliates of Borrower" is deleted in
its entirety and replaced by the following:

         Subsidiaries and Affiliates of Borrower.  Under no circumstances  shall
         this Agreement be construed to require Lender to make any Loan or other
         financial accommodation to any subsidiary or affiliate of Borrower, nor
         shall any  affirmative or negative  covenant or any  representation  or
         warranty  contained in the Loan Documents be construed to be separately
         applicable to any subsidiary or affiliate of Borrower.

Negative Pledge Agreement.  The Negative Pledge Agreement is hereby  terminated,
and neither Lender nor Borrower shall have any further duty or obligation  under
the Negative Pledge Agreement.

12. Unsecured Line of Credit. Lender and Borrower acknowledge and agree that the
Loan is an  unsecured  revolving  line of  credit.  All  references  in the Loan
Documents  to  collateral,  security  interests  and  remedies  with  respect to
collateral are inapplicable,  except to the extent that any advance of credit to
Borrower under the Loan Documents is actually  secured by Borrower's  grant of a
security interest in favor of Lender.

13. Effect of Addendum.  This Addendum amends all of the Loan Documents.  In the
event of a  conflict  in the  provisions  of this  Addendum  and any of the Loan
Documents the provisions of this Addendum shall  control,  and the  inconsistent
Loan Document shall be deemed modified to be consistent here with.

14.  Reaffirmation.  Except as modified  by this  Addendum,  Borrower  reaffirms
Borrower's  obligations to Lender under the Loan Documents,  and agrees to abide
by the terms covenants and conditions thereof.

15.  Successors  and Assigns.  This  Addendum  shall inure to the benefit of and
shall be binding  upon  Lender,  Borrower and their  respective  successors  and
assigns.

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         DATED effective as of the date first above written.

                                    LENDER:
                                    /S/ GEORGE WHITMUR
                                    U.S. BANK NATIONAL ASSOCIATION


                                    BORROWER:
                                    /S/ JOHN T. LEMLEY
                                    EVANS AND SUTHERLAND COMPUTER CORPORATION