We have the 8200 series (SFF and USDT) for quite some time now and only faced an issue once where a card reader was built-in. I mentioned earlier that we had to physically unplug it from the mainboard to avoid conflicts with the mapped network drives for imaging.
Do you also set the remote wakeup source to Remote Server? We configure both parts by default in the BIOS. The EFI optons hould only be relevant if you run a WinPE supporting that, so tht should not matter.
Aside from that, we do rdeploy an IMG image, which wipes the disk and that works consistently so far (expecting the first 8300s' now) and we also do unattended setups for both, WinXP and Win7. Maybe the question is which boot environment you use at the moment? We use DOS and lay down an IMG containing a WinPE environment and so catch partitioning the HDD and also laying down a mini OS, which we can re-use at any time after the machine has finished its silent install of OS, drivers, apss, etc.
Just a comment about AHCI or IDE modes - if you run unattended installs for the OS, you should not have to worry about changing the setting. Again, one of the reasons why I do NOT do sysprep and also do NOPT rely on DeployAnywhere, which - from reading posts in these forums - shows up as causing more issues than helping.
-BBC
PS: I guess, at some point i will have to post the entire process we use for building clients so that whoever wants can consume...