Exhibit 23.1 CONSENT OF INDEPENDENT ACCOUNTANTS We hereby consent to the incorporation by reference in this Post-Effective Amendment No. 1 to Registration Statement on Form S-8 of our report dated April 28, 1999 relating to the financial statements of Adaptec, Inc., which appears in Adaptec, Inc.'s Annual Report on Form 10-K for the year ended March 31, 1999. /s/ PricewaterhouseCoopers LLP San Jose, California December 1, 1999