Method for testing noise of thin-film magnetic head, and magnetic disk drive apparatus with noise testing function

A magnetic disk drive apparatus with a element-testing function, comprising:

• at least one magnetic disk;
• a thin-film magnetic head with a magnetoresistive effect read head element for reading out data signal from said at least one magnetic disk, and a heating unit capable of applying a heat and a stress to said magnetoresistive effect read head element;
• a support member for supporting said thin-film magnetic head;
• means for applying alternately and discontinuously with each other an electrical power having a first level and an electrical power having a second level higher than said first level to said heating unit;
• and
• means for evaluating said thin-film magnetic head by measuring a noise output or noise outputs obtained from said magnetoresistive effect read head element when the electrical power or the electrical powers are applied to said heating unit.