1. Did you check the Device Manager to see if the PS/2 Mouse and Keyboard have a Power Management Option tab to allow the device to wake the system from Standby? If so, is the box checked?
2. How long do you usually wait before initiating resume from sleep? Hybrid sleep takes a long time to initiate.
What you should look for..
1. Initiate standby
2. Watch the system as it is entering standby...
3. The system provides and indication that the system is in standby (e.g. blinking power led or power led changes color)
4. Then you must watch the HDD LED, the system writes the contents from memory (2GB) to HDD. When that completes, you will see the HDD LED turn off.
5. You will hear the HDD spin down/turn off
6. Now you're in hybrid sleep
7. Wake the system and see if it wakes up.