Windows 7 - PC wakes immediately from sleep...

Ive found the solution to the problem and thought i would post it back here to share with all. Anyone with a later model of an ASUS motherboard will find that this is the answer:

It is as i expected above, the BIOS was forcing the computer to wake back up because the USB device wakeup jumpers were set to "1-2" instead of "2-3" which basically means that there was no power going to the USB Device Wakeup for the computer to sleep hence why it keeps waking the computer up.
To clarify further to any readers, there is an S1 sleep function and an S3, S1 puts the computer in a low power state with tasks still running though whereas S3 is a complete sleep i.e. no tasks running. When you set the jumpers on the USB device wakeup to "2-3" then you are enabling the S3 mode which is what you want .

Very good... as an ASUS owner myself, I appreciate the info!

No problem , i carefully read through the manual again and i was like ohhhhhh i think i get it now lol.
Just bare in mind that on an ASUS there are 3 jumpers you might want to consider replacing:
1- Keyboard wakeup jumper (Not 100% sure but i think they mean PS2 by this)
2- USB device wakeup jumper (which is right next to the keyboard jumper)
3- USB device wakeup jumper (which is next to the actual USBs)

I believe that "2" will make the rear USB ports wake up the computer and "3" will make the front USB ports wakeup the computer.

Whether i only needed to change the jumpers on "2" only i dont know i couldnt be arsed to test it since its hard to change the jumpers without needle nose plyers . I just replaced all 3 jumpers to give them power supply.

I'm pretty sure the jumper layouts are different for each board, but you did prompt me to look at my own MB Manual and switch the jumpers over.

The behavioral change is interesting... on the 2-3 pins the USB device no longer wakes the system up, but they are recognized instantly when I wiggle the mouse... In the 1-2 positions plugging in a thumb drive would wake the computer but it would take sometimes half a minute to figure out what I did to it...

Yes the keyboard jumper thing refers to PS2 keyboard and mouse... and on my MB there is also a BIOS setting that overrides the jumper setting...

And I will say, I like the S3 standby a lot better... the computer is completely silent, no fans running... My room is sooooo peaceful... well until somebody does something on the lan that wakes it up...

Yeh i find it very strange that ASUS didnt consider people would want to use the S3 as a default, perhaps they just wanted to make sure that when users wanted to use the feature they knew what they were doing to supply it enough power to use the function (because says in the manual it needs a specific source of power to work) - but yet again what power supply wouldnt be able to supply that hehe.

Much like Windows itself, motherboards are generally supplied in a "most likely to work" configuration. When they make them they might assume Windows but they don't actually know for certain what OS will be installed, so they have to make sure they'll boot almost anything. S1 is pretty safe as a default... as are the Auto settings for most everything...

I think it's pretty fair to say that most users (as opposed to the clan here) never look in their BIOS and most install and run their software entirely on defaults. So things have to be in a "most likely to work" state or the whole thing comes crashing down.

Looking at the specs for my power supply... the 5volt standby supply only delivers 2 amps... enough for three ports and the motherboard itself.