diff --git a/scripts/wk/hw/diags.py b/scripts/wk/hw/diags.py
index edb2d3be..8c8abfad 100644
--- a/scripts/wk/hw/diags.py
+++ b/scripts/wk/hw/diags.py
@@ -1290,7 +1290,10 @@ def ost_build_report(dev, dev_type):
   # Description
   report.append(dev.description)
   if hasattr(dev, 'ram_total'):
-    report.append(f'{dev.ram_total} ({", ".join(dev.ram_dimms)})')
+    if len(dev.ram_dimms) == 1 and 'justTotalRAM' in dev.ram_dimms[0]:
+      report.append(f'{dev.ram_total} (Total - no DIMM info available)')
+    else:
+      report.append(f'{dev.ram_total} ({", ".join(dev.ram_dimms)})')
   if hasattr(dev, 'serial') and dev.serial:
     report.append(f'Serial Number: {dev.serial}')
   report.append('')
diff --git a/scripts/wk/hw/obj.py b/scripts/wk/hw/obj.py
index 4a00fd52..bf6eef37 100644
--- a/scripts/wk/hw/obj.py
+++ b/scripts/wk/hw/obj.py
@@ -2,6 +2,7 @@
 # vim: sts=2 sw=2 ts=2
 
 import logging
+import os
 import pathlib
 import plistlib
 import re
@@ -151,11 +152,13 @@ class CpuRam(BaseObj):
 
   def get_serial_number(self):
     if PLATFORM == 'Darwin':
-      cmd = ['system_profiler', 'SPHardwareDataType']
-      proc = run_program(cmd, check=False)
-      match = MAC_SERIAL_REGEX.search(proc.stdout)
-      if match:
-        self.serial = match['serial'].strip()
+      cmd = (
+        'ioreg -c IOPlatformExpertDevice -d 2'
+        "| awk '/IOPlatformSerialNumber/ {print $3}'"
+        '| sed s/"//g'
+        )
+      proc = run_program(cmd, check=False, shell=True)
+      self.serial = proc.stdout.strip()
 
 
 class Disk(BaseObj):
@@ -815,6 +818,25 @@ def get_ram_list_linux():
 
 
 def get_ram_list_macos():
+  """Get RAM list under macOS."""
+  if os.path.exists('/usr/sbin/system_profiler'):
+    return get_ram_list_system_profiler()
+
+  # Failback option
+  return get_ram_list_sysctl()
+
+
+def get_ram_list_sysctl():
+  """Get RAM list using sysctl."""
+  cmd = ['sysctl', '-n', 'hw.memsize']
+  proc = run_program(cmd)
+  return [[
+    int(proc.stdout.strip()),
+    'justTotalRAM',
+    ]]
+
+
+def get_ram_list_system_profiler():
   """Get RAM list using system_profiler."""
   dimm_list = []