Windows 7 - Memory - Set Maximum Amount Used by Windows 7

followed step 1-4, and 6-8 precisely, all seems to take ok, but after system reboot:
Task Manager shows Total 4094MB.
Control Panel/System shows:
Windows7Professional, ServicePack1
Installed memory: 8.00GB(4.00GB useable)
System type: 64-bit Operating system

any ideas why it doesnt work? Works ok on another 64bit system I have.
Resource Monitor/Memory shows:
Hardware Reserved: 4098MB
In Use: 1259MB
Modified: 108MB

Standby: 1521MB
Free: 1207MB
Available: 2727MB
Cached: 1629MB
Total: 4094MB
Installed: 8192MB

No Integrated Graphics.
Bios is Version AMI 1208, 07/30/10
Bios under Main/ System Memory states:
Usable Size: 4095MB
MB: Asus P7P55D-ELX
Intel i7
Cant find anything in Bios to change Memory Size??

Hello Harald,

Double check the items in the red warning box at the top of the tutorial to see if any may apply to you in your BIOS settings.

Solution: on MB: Asus P7P55D-ELX
Turned out to be a memory/Bios Setting issue:
8GB(4x2GB)installed, Bios and Win7_64 shows only 4GB, 4GB hardware reserved
Finally got it to work with 8GB:
What I did:
Power off
Clear CMOS: Short CLRT pins on MB, short pin2,3:, (Not just reload defaults in BIOS), and back to Normal: short Pin1,2
Press MemOK, a Asus MB feature that sets Memory timing parameters automatically
Power on
Delete, to get into BIOS:
Now BIOS/Main/System Info: Usable Size: 8191MB (and Win7_64 reports 8GB)
Note: unless Bios shows correct size, Windows wont see it.(even though CPU-Z will report it).
I had tried all else without luck. Key was to hardware clear CMOS on MB.

That's great news Harald. I'm happy to hear that you got it sorted. Thank you for posting back with your results and solution.