Do Sata II drives work with ASUS A8N SLI deluxe MOBO or just SATA I?

Yes, they work. However, stay away from Maxtor series 9 and 10 drives.

How does one check if the hdd is operating in SATA 1 or Sata 2? There is a question on the ASUS FAQ that makes me wonder, though I can't find that info in device manager:

Question:
I'm using Hitachi 80G SATAII HDD on my A8N-SLI Deluxe. After installing NVIDIA chipset driver, I can only see HDD with SATA1 support (150MB/s) under Device Manager. Why?

Answer:
This is because the HDD vendor will often set SATA1 as default value for their new SATAII HDD. Hitachi also releases a tool named "Feature Tool" for changing the settings to SATA II. Please refer to the following link on Hitachi 's website for detail.
http://www.hitachigst.com/hdd/support/download.htm

Nice find! By the way, the drive will produce between 70 and 80 mb/s in either mode, so that setting does not matter one bit.

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