diff --git a/src/device/cpu_device.c b/src/device/cpu_device.c
index 072d7c6844..ccbe6ec7da 100644
--- a/src/device/cpu_device.c
+++ b/src/device/cpu_device.c
@@ -22,7 +22,7 @@ device_t add_cpu_device(struct bus *cpu_bus, unsigned apic_id, int enabled)
 	struct device_path cpu_path;
 	device_t cpu;
 
-	/* Build the cpu device path */
+	/* Build the CPU device path */
 	cpu_path.type = DEVICE_PATH_APIC;
 	cpu_path.apic.apic_id = apic_id;
 
diff --git a/src/device/oprom/realmode/x86_asm.S b/src/device/oprom/realmode/x86_asm.S
index b90aaa4403..2bb2a3f053 100644
--- a/src/device/oprom/realmode/x86_asm.S
+++ b/src/device/oprom/realmode/x86_asm.S
@@ -143,7 +143,7 @@ __realmode_call:
 	mov	%ax, %ds
 	lidt	__realmode_idt
 
-	/* initialize registers for option rom lcall */
+	/* initialize registers for option ROM lcall */
 	movl	__registers +  0, %eax
 	movl	__registers +  4, %ebx
 	movl	__registers +  8, %ecx
diff --git a/src/device/oprom/yabel/debug.h b/src/device/oprom/yabel/debug.h
index 60d4c47ec3..b1a860072d 100644
--- a/src/device/oprom/yabel/debug.h
+++ b/src/device/oprom/yabel/debug.h
@@ -71,7 +71,7 @@ static inline void set_ci(void) {};
  * ||||||||||-DEBUG_PRINT_INT10 - let INT10 (i.e. character output) calls print messages to Debug output
  * |||||||||||-DEBUG_INTR - Print messages related to interrupt handling
  * ||||||||||||-DEBUG_CHECK_VMEM_ACCESS - Print messages related to accesse to certain areas of the virtual Memory (e.g. BDA (BIOS Data Area) or Interrupt Vectors)
- * |||||||||||||-DEBUG_MEM - Print memory access made by option rom (NOTE: this also includes accesses to fetch instructions)
+ * |||||||||||||-DEBUG_MEM - Print memory access made by option ROM (NOTE: this also includes accesses to fetch instructions)
  * ||||||||||||||-DEBUG_IO - Print I/O access made by option rom
  * 11000111111111 - Max Binary Value, Debug All (WARNING: - This could run for hours)
  */