diff --git a/repbuild/src/main.rs b/repbuild/src/main.rs
index ba519db..7ae36d7 100644
--- a/repbuild/src/main.rs
+++ b/repbuild/src/main.rs
@@ -429,6 +429,8 @@ fn run(release: bool, target: Target, do_accel: bool) -> Result<(), Error> {
         let vmx = cpuid.get_feature_info().unwrap().has_vmx();
         let svm = cpuid.get_svm_info().is_some();
 
+        let mut cpu = "max";
+
         if supported.contains("kvm") && (vmx || svm) {
             "accel=kvm"
         } else if cpuid
@@ -440,6 +442,7 @@ fn run(release: bool, target: Target, do_accel: bool) -> Result<(), Error> {
         {
             "accel=hax"
         } else if supported.contains("whpx") {
+            cpu = "Westmere";
             "accel=whpx,kernel-irqchip=off"
         } else {
             "accel=tcg"
@@ -464,7 +467,7 @@ fn run(release: bool, target: Target, do_accel: bool) -> Result<(), Error> {
                 "-parallel", "none",
                 "-monitor", "none",
                 "-machine", accel,
-                "-cpu", "max",
+                "-cpu", cpu,
                 "-device", "isa-debug-exit,iobase=0xf4,iosize=0x04",
             ]);
         }