diff --git a/arch/i386/boot/apm.c b/arch/i386/boot/apm.c
index a34087c..5843beb 100644
--- a/arch/i386/boot/apm.c
+++ b/arch/i386/boot/apm.c
@@ -34,6 +34,9 @@ int query_apm_bios(void)
 		     : "=d" (err), "+a" (ax), "+b" (bx), "+c" (cx)
 		     : : "esi", "edi");
 
+	printf("apm: err = %d, ax = %#x, bx = %#x, cx = %#x\n",
+	       err, ax, bx, cx);
+
 	if (err)
 		return -1;		/* No APM BIOS */
 
@@ -45,9 +48,10 @@ int query_apm_bios(void)
 
 	/* Disconnect first, just in case */
 	ax = 0x5304;
+	bx = 0;
 	asm volatile("pushl %%ebp ; int $0x15 ; popl %%ebp"
-		     : "+a" (ax)
-		     : : "ebx", "ecx", "edx", "esi", "edi");
+		     : "+a" (ax), "+b" (bx)
+		     : "ecx", "edx", "esi", "edi");
 
 	/* Paranoia */
 	ebx = esi = 0;
@@ -59,6 +63,10 @@ int query_apm_bios(void)
 		       "+S" (esi), "+D" (di), "=m" (err)
 		     : "a" (0x5303));
 
+	printf("apm: err = %d, ax = %#x, ebx = %#x, cx = %#x, dx = %#x\n"
+	       "     esi = %#x, di = %#x\n",
+	       err, ax, ebx, cx, dx, esi, di);
+
 	boot_params.apm_bios_info.cseg = ax;
 	boot_params.apm_bios_info.offset = ebx;
 	boot_params.apm_bios_info.cseg_16 = cx;
@@ -79,6 +87,9 @@ int query_apm_bios(void)
 		     : "=d" (err), "+a" (ax), "+b" (bx), "+c" (cx)
 		     : : "esi", "edi");
 
+	printf("apm: err = %d, ax = %#x, bx = %#x, cx = %#x\n",
+	       err, ax, bx, cx);
+
 	if (err || bx != 0x504d) {
 		/* Failure with 32-bit connect, try to disconect and ignore */
 		ax = 0x5304;
diff --git a/arch/i386/boot/main.c b/arch/i386/boot/main.c
index 7f01f96..b0072d7 100644
--- a/arch/i386/boot/main.c
+++ b/arch/i386/boot/main.c
@@ -150,6 +150,8 @@ void main(void)
 	/* Query APM information */
 #if defined(CONFIG_APM) || defined(CONFIG_APM_MODULE)
 	query_apm_bios();
+#else
+	printf("apm: disabled\n");
 #endif
 
 	/* Query EDD information */