How have courts dealt with the issue of prior convictions that can be used for sentence enhancement purposes?

To the extent Dennis argues that his enhanced sentence based on prior convictions is illegal because the state never filed notice of the priors, the district court properly denied this claim as noncognizable. See United States v. McDoughtery, 920 F.2d 569, 575 (9th Cir.1990) (due process not violated when prior convictions are alleged in presentence report and proven by a preponderance of evidence), cert. denied, 499 U.S. 911 (1991); United States v. Dunn, 946 F.2d 615, 619 (9th Cir.) (prior convictions used for sentence enhancement purposes need not be charged in the indictment), cert. denied, 112 S.Ct. 401 (1991).