Dell Optiplex GX520 A11

I found the thread for the optiplex GX520 A06:
http://www.bios-mods.com/forum/Thread-De...l-SLIC-2-1
This fails to activate windows 7 32 and 64 bit even when it correctly says Slic 2.1 DELLM09

The dell original bios file is here.
http://www.dell.com/support/drivers/us/e...egoryId=BI

Any help is appriciated!