diff --git a/builder/hyperv/vmcx/builder.go b/builder/hyperv/vmcx/builder.go
index 546d5c80a..24785cc0d 100644
--- a/builder/hyperv/vmcx/builder.go
+++ b/builder/hyperv/vmcx/builder.go
@@ -21,10 +21,10 @@ import (
 )
 
 const (
-	DefaultRamSize                 = 1 * 1024  // 1GB
-	MinRamSize                     = 32        // 32MB
-	MaxRamSize                     = 64 * 1024 // 64GB
-	MinNestedVirtualizationRamSize = 4 * 1024  // 4GB
+	DefaultRamSize                 = 1 * 1024    // 1GB
+	MinRamSize                     = 32          // 32MB
+	MaxRamSize                     = 1024 * 1024 // 1TB
+	MinNestedVirtualizationRamSize = 4 * 1024    // 4GB
 
 	LowRam = 256 // 256MB