When you went to update the bios you have simply seen an incomplete flash of the eprom. The only time you should contact support is generally for replacement. But you can also specify it be reflashed for the costs of shipping and receiving the chip as well as the tool needed for reinserting it later. One goof there and you are without a board. That's something to consider since a chip is a delicate item.
You are better off trying a slightly older but not 0701 version to reflash with. This way you getting an update and another chance there. When using the product/type/model selector at the Asus support site you have a P5W DH Deluxe board is that correct? You left out the DH. The bios download page is seen at
http://support.asus.com/download/download.aspx?SLanguage=en-us
You will find the latest you can try to redo or go with something like the 1801 beta or 1401 version. You probably saw a bad flash or there is some other reason for seeing the drive slow down. The updated version generally sees an improvement when it goes on good.