<Page>

                                                                    EXHIBIT 10.5

                                 PROMISSORY NOTE

<Table>
<Caption>
     PRINCIPAL     LOAN DATE      MATURITY      LOAN NO.     CALL/COLL     ACCOUNT     OFFICER     INITIALS
 <S>               <C>           <C>            <C>          <C>           <C>           <C>       <C>
 $ 3,300,075.00    07-16-2001    01-20-2009     30356872                   8303568       22
</Table>

  References in the shaded area are for Lender's use only and do not limit the
 applicability of this document to any particular loan or item. Any item above
       containing ***** has been omitted due to text length limitations.

<Table>
<S>                                                         <C>
BORROWER:  LOS ALAMOS NATIONAL BANK EMPLOYEE STOCK          LENDER:   Valley National Bank
           OWNERSHIP PLAN                                             322 Riverside Drive
           P O BOX 60                                                 P O Box 99
           LOS ALAMOS, NM 87544                                       Espanola, NM 87532
</Table>

<Table>
<S>                                            <C>                              <C>
PRINCIPAL AMOUNT: $3,300,075.00                INITIAL RATE: 6.750%             DATE OF NOTE: July 16, 2001
</Table>

PROMISE TO PAY LOS ALAMOS NATIONAL BANK EMPLOYEE STOCK OWNERSHIP PLAN
("Borrower") promises to pay to Valley National Bank ("Lender" for order, in
lawful money of the United States of America, the principal amount to Three
Million Three Hundred Thousand Seventy-five & 90/100 Dollars ($3,300,075.00),
together with interest on the unpaid principal balance from July 16, 2001, until
paid in full.

PAYMENT. Subject to any payment changes resulting from changes in the index,
Borrower will pay this loan in accordance with the following payment schedule:

     SEMI-ANNUAL INTEREST PAYMENTS DUE 1-20-2002 AND EVERY SIX MONTHS
     THEREAFTER. ANNUAL PRINCIPAL PAYMENTS OF $471,439.29 DUE EACH YEAR UNTIL
     PAID IN FULL OR 01-20-2008.

Unless otherwise agreed or required by applicable law, payments will be applied
first to accrued unpaid interest, then to principal, and any remaining amount to
any unpaid collection costs. Interest on this Note is computed on a 365/365
simple interest basis; that is, by applying the ratio of the annual interest
rate over the number of days in a year, multiplied by the outstanding principal
balance, multiplied by the actual number of days the principal balance is
outstanding. Borrower will pay Lender at Lender's address shown above or at such
other place as Lender may designate in writing.

VARIABLE INTEREST RATE. The interest rate on this Note is subject to change from
time to time based on changes in an independent index which is the CITI BANK
PRIME (the "Index"). The Index is not necessarily the lowest rate charged by
Lender on its loans. If the Index becomes unavailable during the term of this
loan, Lender may designate a substitute index after notice to Borrower. Lender
will tell Borrower the current Index rate upon Borrower's request. The interest
rate change will not occur more often than each DAILY. Borrower understands that
Lender may make loans based on other rates as well. THE INDEX CURRENTLY IS
6.750% PER ANNUM. THE INTEREST RATE TO BE APPLIED TO THE UNPAID PRINCIPAL
BALANCE OF THIS NOTE WILL BE AT THE RATE EQUAL TO THE INDEX, RESULTING IN AN
INITIAL RATE OF 6.750% PER ANNUM. NOTICE. Under no circumstances will the
interest rate on this Note be more than the maximum rate allowed by applicable
law. Whenever increases occur in the interest rate, Lender, at its option, may
do one or more of the following: (A) increase Borrower's payment to ensure
Borrower's loan will pay off by its original final maturity date, (B) increase
Borrower's payments to cover accruing interest, (C) increase the number of
Borrower's payments, and (D) continue Borrower's payments at the same amount and
increase Borrower's final payment.

PREPAYMENT; MINIMUM INTEREST CHARGE. In any event, even upon full prepayment of
this Note, Borrower understands that Lender is entitled TO A MINIMUM INTEREST
CHARGE ON $10.00. Other than Borrower's obligation to pay any minimum interest
charge, Borrower may pay without penalty all or a portion of the amount owed
earlier than its is due. Early payments will not, unless agreed to by Lender in
writing, relieve Borrower or Borrower's obligation to continue to make payments
under the payments schedule. Rather, early payments will reduce the principal
balance due and may result in Borrower's making fewer payments. Borrower agrees
not to send Lender payments marked "paid in full", "without recourse", or
similar language. If Borrower sends such a payment, Lender may accept it without
losing any of Lender's rights under this Note, and Borrower will remain
obligated to pay any further amount owed to Lender. All written communications
concerning disputed amounts, including any check or other payment instrument
that indicates that the payment constitutes "payment in full" of the amount owed
or that is tendered with other conditions or limitations or as full satisfaction
of a disputed amount must be mailed or delivered to: Valley National Bank, 322
Riverside Drive Espanola, NM 87532.

INTEREST AFTER DEFAULT. Upon default, including failure to pay upon final
maturity, the total sum due under this Note will bear interest from the date of
acceleration or maturity at the variable interest rate on this Note. The
interest rate will not exceed the maximum rate permitted by applicable law.

DEFAULT. Each of the following shall constitute an event of default ("Event of
Default") under this Note:

     PAYMENT DEFAULT. Borrower fails to make any payment when due under this
     Note.

     OTHER DEFAULTS. Borrower fails to comply with or to perform any other term,
     obligation, covenant or condition contained in this Note or in any of the
     related documents or to comply with or to perform any term, obligation,
     covenant or condition contained in any other agreement between Lender and
     Borrower.

     FALSE STATEMENTS. Any warranty, representation or statement made or
     furnished to Lender by Borrower or on Borrower's behalf under this Note or
     the related documents is false or misleading in any material respect,
     either now or at the time made or furnished or becomes false or misleading
     at any time thereafter.

     INSOLVENCY. The dissolution or termination of Borrower's existence as a
     going business, the insolvency of Borrower, the appointment of a receiver
     for any part of Borrower's property, any assignment for the benefit of
     creditors, any type of creditor workout, or the commencement of any
     proceeding under any bankruptcy or insolvency laws by or against Borrower.

     CREDITOR OR FORFEITURE PROCEEDINGS. Commencement of foreclosure or
     forfeiture proceedings, whether by judicial proceeding, self-help,
     repossession of any other method, by any creditor of Borrower or by any
     governmental agency against any collateral securing the loan. This includes
     a garnishment of any of Borrower's accounts, including deposit accounts,
     with Lender. However, this Event of Default shall not apply if there is a
     good faith dispute by Borrower as to the validity or reasonableness of the
     claim which is the basis of the creditor or forfeiture proceeding and if
     Borrower gives Lender written notice of the creditor or forfeiture
     proceeding and deposits with Lender monies or a surety bond for the
     creditor or forfeiture proceeding, in an amount determined by Lender, in
     its sole discretion, as being as adequate reserve or bond for the dispute.

     EVENTS AFFECTING GUARANTOR. Any of the preceding events occurs with respect
     to any guarantor, endorser, surety, or accommodation party of any of the
     indebtedness or any guarantor, endorser, surety, or accommodation party
     dies or becomes incompetent, or revokes or disputes the validity of, or
     liability under, any guaranty of the indebtedness evidenced by this Note.
     In the event of a death, Lender, at its option, may, but shall not be
     required to permit the guarantor's estate to assume unconditionally the
     obligations arising under the guaranty in a manner satisfactory to Lender,
     and, in doing so, cure any Event of Default.

     CHANGE IN OWNERSHIP. Any change in ownership of twenty-five percent (25%)
     or more of the common stock of Borrower.

     ADVERSE CHANGE. A material adverse change occurs in Borrower's financial
     condition, or Lender believes the prospect of payment or performance of
     this Note is impaired.

<Page>

                                PROMISSORY NOTE
LOAN NO: 30356872                  (CONTINUED)                            PAGE 2

     Insecurity.  Lender in good faith believes itself insecure.

     Cure Provisions. If any default, other than a default in payment or failure
     to satisfy Lender's requirement in the insufficient Market Value of
     Securities section is curable and if Borrower has not been given a notice
     of a breach of the same provision of this Note within the preceding twelve
     (12) months. it may be cured (and no event of default will have occurred)
     if Borrower, after receiving written notice from Lender demanding cure of
     such default: (1) cures the default within fifteen (15) days; or (2) if the
     cure requires more than fifteen (15) days, immediately initiates steps
     which Lender deems in Lender's sole discretion to be sufficient to cure the
     default and thereafter continues and completes all reasonable and necessary
     steps sufficient to produce compliance as soon as reasonably practical.

LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid principal
balance on this Note and all accrued unpaid interest immediately due, and then
Borrower will pay that amount.

ATTORNEYS' FEES; EXPENSES. Lender may hire or pay someone else to help collect
this Note if Borrower does not pay. Borrower will pay Lender that amount. This
includes, subject to any limits under applicable law, Lender's attorneys' fees
and Lender's legal expenses, whether or not there is a lawsuit, including
attorneys' fees, expenses for bankruptcy proceedings (including efforts to
modify or vacate any automatic stay or injunction), and appeals. If not
prohibited by applicable law, Borrower also will pay any court costs, in
addition to all other sums provided by law.

GOVERNING LAW. THIS NOTE WILL BE GOVERNED BY, CONSTRUED AND ENFORCED IN
ACCORDANCE WITH FEDERAL LAW AND THE LAWS OF THE STATE OF NEW MEXICO. THIS NOTE
HAS BEEN ACCEPTED BY LENDER IN THE STATE OF NEW MEXICO.

DISHONORED ITEM FEE. Borrower will pay a fee to Lender of $18.00 if Borrower
makes a payment on Borrower's loan and the check or preauthorized charge with
which Borrower pays is later dishonored.

RIGHT OF SETOFF. To the extent permitted by applicable law, Lender reserves a
right of setoff in all Borrower's accounts with Lender (whether checking,
savings, or some other account). This includes all accounts Borrower holds
jointly with someone else and all accounts Borrower may open in the future.
However, this does not include any IRA or Keogh accounts, or any trust accounts
for which setoff would be prohibited by law. Borrower authorizes Lender, to the
extent permitted by applicable law, to charge or setoff all sums owing on the
indebtedness against any and all such accounts.

COLLATERAL. Borrower acknowledges this Note is secured by ASSIGNMENT OF SHARES
OF TRINITY CAPITAL CORP. STOCK CERT. # 04353 @ 62,000 SHARES OF CAPITAL STOCK.
STOCK CERT# 4593 @ 13,020 SHARES OF CAPITAL STOCK. STOCK CERT#4589 @ 48,704
SHARES OF CAPITAL STOCK.

ARBITRATION. BORROWER AND LENDER AGREE THAT ALL DISPUTES, CLAIMS AND
CONTROVERSIES BETWEEN THEM WHETHER INDIVIDUAL, JOINT, OR CLASS IN NATURE,
ARISING FROM THIS NOTE OR OTHERWISE, INCLUDING WITHOUT LIMITATION CONTRACT AND
TORT DISPUTES, SHALL BE ARBITRATED PURSUANT TO THE RULES OF THE AMERICAN
ARBITRATION ASSOCIATION IN EFFECT AT THE TIME THE CLAIM IS FILED, UPON REQUEST
OF EITHER PARTY. NO ACT TO TAKE OR DISPOSE OF ANY COLLATERAL SECURING THIS NOTE
SHALL CONSTITUTE A WAIVER OF THIS ARBITRATION AGREEMENT OR BE PROHIBITED BY THIS
ARBITRATION AGREEMENT. THIS INCLUDES, WITHOUT LIMITATION, OBTAINING INJUNCTIVE
RELIEF OR A TEMPORARY RESTRAINING ORDER; INVOKING A POWER OF SALE UNDER ANY DEED
OF TRUST OR MORTGAGE; OBTAINING A WRIT OF ATTACHMENT OR IMPOSITION OF A
RECEIVER; OR EXERCISING ANY RIGHTS RELATING TO PERSONAL PROPERTY, INCLUDING
TAKING OR DISPOSING OF SUCH PROPERTY WITH OR WITHOUT JUDICIAL PROCESS PURSUANT
TO ARTICLE 9 OF THE UNIFORM COMMERCIAL CODE. ANY DISPUTES, CLAIMS, OR
CONTROVERSIES CONCERNING THE LAWFULNESS OR REASONABLENESS OF ANY ACT, OR
EXERCISE OF ANY RIGHT, CONCERNING ANY COLLATERAL SECURING THIS NOTE, INCLUDING
ANY CLAIM TO RESCIND, REFORM, OR OTHERWISE MODIFY ANY AGREEMENT RELATING TO THE
COLLATERAL SECURING THIS NOTE, SHALL ALSO BE ARBITRATED, PROVIDED HOWEVER THAT
NO ARBITRATOR SHALL HAVE THE RIGHT OR THE POWER TO ENJOIN OR RESTRAIN ANY ACT OF
ANY PARTY. JUDGMENT UPON ANY AWARD RENDERED BY ANY ARBITRATOR MAY BE ENTERED IN
ANY COURT HAVING JURISDICTION. NOTHING IN THIS NOTE SHALL PRECLUDE ANY PARTY
FROM SEEKING EQUITABLE RELIEF FROM A COURT OF COMPETENT JURISDICTION. THE
STATUTE OF LIMITATIONS, ESTOPPEL, WAIVER, LACHES, AND SIMILAR DOCTRINES WHICH
WOULD OTHERWISE BE APPLICABLE IN AN ACTION BROUGHT BY A PARTY SHALL BE
APPLICABLE IN ANY ARBITRATION PROCEEDING, AND THE COMMENCEMENT OF AN ARBITRATION
PROCEEDING SHALL BE DEEMED THE COMMENCEMENT OF AN ACTION FOR THESE PURPOSES. THE
FEDERAL ARBITRATION ACT SHALL APPLY TO THE CONSTRUCTION, INTERPRETATION, AND
ENFORCEMENT OF THIS ARBITRATION PROVISION.

SUCCESSOR INTERESTS. The terms of this Note shall be binding upon Borrower, and
upon Borrower's heirs, personal representatives, successors and assigns, and
shall inure to the benefit of Lender and its successors and assigns.

NOTIFY US OF INACCURATE INFORMATION WE REPORT TO CONSUMER REPORTING AGENCIES.
Please notify us if we report any inaccurate information about your account(s)
to a consumer reporting agency. Your written notice describing the specific
inaccuracy(ies) should be sent to us at the following address: Valley National
Bank, 322 Riverside Drive, P O Box 99, Espanola, NM 87532

GENERAL PROVISIONS. Lender may delay or forgo enforcing any of its rights or
remedies under this Note without losing them. Borrower and any other person who
signs, guarantees or endorses this Note, to the extent allowed by law, waive
presentment, demand for payment, and notice of dishonor. Upon any change in the
terms of this Note, and unless otherwise expressly stated in writing, no party
who signs this Note, whether as maker, guarantor, accommodation maker or
endorser, shall be released from liability. All such parties agree that Lender
may renew or extend (repeatedly and for any length or time) this loan or release
any party or guarantor or collateral; or impair, fail to realize upon or perfect
Lender's security interest in the collateral; and take any other action deemed
necessary by Lender without the consent of or notice to anyone. All such
parties also agree that Lender may modify this loan without the consent of or
notice to anyone other than the party with whom the modification is made. The
obligations under this Note are joint and several.

PRIOR TO SIGNING THIS NOTE, BORROWER READ AND UNDERSTOOD ALL THE PROVISIONS OF
THIS NOTE, INCLUDING THE VARIABLE INTEREST RATE PROVISIONS. BORROWER AGREES TO
THE TERMS OF THE NOTE.

BORROWER ACKNOWLEDGES RECEIPT OF A COMPLETED COPY OF THIS PROMISSORY NOTE.

BORROWER:


LOS ALAMOS NATIONAL BANK EMPLOYEE STOCK OWNERSHIP PLAN

By: /s/ Sharon Watson
   -----------------------------------------
   SHARON WATSON, V.P AND TRUST OFFICER of
   LOS ALAMOS NATIONAL BANK EMPLOYEE STOCK
   OWNERSHIP PLAN


<Page>

                                PROMISSORY NOTE
LOAN NO: 30356872                  (CONTINUED)                            PAGE 3

LENDER:

VALLEY NATIONAL BANK


X
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  Authorized Signer

                                   [ILLEGIBLE]