Sigma Designs (SIGM) 10-Q 2009 Q2 Quarterly report

Exhibit 18.1

September 11, 2008

Board of Directors

Sigma Designs, Inc

1778 McCarthy Blvd.

Milpitas, CA 95035

Dear Directors:

We are providing this letter to you for inclusion as an exhibit to your Form 10-Q filing pursuant to Item 601 of Regulation S-K.

We have been provided a copy of the Company’s Quarterly Report on Form 10-Q for the period ended August 2, 2008. Note 2 therein describes a change in accounting principle related to the method used to value the portion of its raw materials known as tested wafers or “die bank”.  It should be understood that the preferability of one acceptable method of accounting over another for inventory costing has not been addressed in any authoritative accounting literature, and in expressing our concurrence below we have relied on management’s determination that this change in accounting principle is preferable. Based on our reading of management’s stated reasons and justification for this change in accounting principle in the Form 10-Q, and our discussions with management as to their judgment about the relevant business planning factors relating to the change, we concur with management that such change represents, in the Company’s circumstances, the adoption of a preferable accounting principle in conformity with Statement of Financial Accounting Standards No. 154, Accounting Changes and Error Corrections.

We have not audited any financial statements of the Company as of any date or for any period subsequent to February 2, 2008. Accordingly, our comments are subject to change upon completion of an audit of the financial statements covering the period of the accounting change.

Very truly yours,

Armanino McKenna LLP