Try clearing CMOS using this method:

http://forum.asrock.com/forum_posts.asp?TID=630&title=how-to-clear-cmos-via-battery-removal

If that does not work then return the board to your supplier again. It sounds like you may have been sent a defective board by the reseller when you returned the first one. Many resellers will "test" a returned board then send it back out to another client if it passes their tests. Sadly, all too often, the job of testing these boards falls to inexperienced techs or overworked support staff and things are overlooked. I am guessing by the fact that you were made to "pay" for the second board, your place of purchase is not very large. Most outlets will write off the cost of a return as being within acceptable losses to keep a customer happy (in the case where the original product is not returned or is lost in shipping). When it comes to buying PC parts it always pays to buy from reputable sources. Many small, independent resellers engage in shady practices like buying "factory reject" products and selling them on to clients for a larger profit or at reduced (tempting) prices. Your initial issue with the first board for example, a lot of people would not have bothered with a return if the rest of the board functioned correctly. 

Every manufacturer has a few boards that fail/don't work correctly from time to time, it just sucks to be the recipient of one. If you have a look around the forums here you will see that this does not happen very often, especially when you consider these forums are international. Rest assured, you simply got unlucky. ASRock will typically bend over backwards to help you. I have seldom seen such devotion to customer satisfaction which is why I stuck around on these forums and was subsequently invited to be a moderator here.

If you have further issues, please contact me via PM with the name of your place of purchase and your country of origin. I will pass this along to my contacts at ASRock and see if they can assist you further and perhaps investigate your reseller. 

Is this board refurbished

Boards sent out as replacements by ASRock are almost always new, in some cases when a board passes the entire barrage of quality control tests for a second time or the issue with it was a corrupted BIOS etc it will be sent out to a client but in all these situations, these boards are thoroughly tested (more so than even new production boards) beforehand. As I said before however, it sounds like your replacement came from your place of purchase, not ASRock directly. This is common practice with most resellers, they will send you a replacement from their own stock, send your damaged product to the manufacture then receive and resell the replacement. Problems arise when they instead try to repair the products in house and sell/resend these. No reseller is equipped to perform the degree of testing that the manufacturer can.

Don't get me wrong, I am not defending ASRock here, I am simply trying to outline common issues with resellers and untoward practices that often get blamed on product manufacturers.

I couldn't agree more 

There is literally NO motherboard manufacturer that has this bad of a failure rate. If all the boards had related issues then it may be possible that a bad batch found it's way onto the store shelves (typically caused by a bad batch of specific components) but with so many, vastly different, issues the most likely culprit is the store engaging in questionable practices