That is a relative judgement. The motherboard is one of the more expensive parts of a computer. On the other hand, it's cheaper than a whole new computer. Also, they vary in price, depending on the processor and the quality and features of the board. Prices (US, early 2011) range from $70 to $300 (not including processor and memory).
Depends on the type of work it is intended for. For example, expensive motherboards are not necessary for word processing alone, while expensive motherboards will be required for high graphics, the heavier the workload and the more games are to be played, well, motherboards cannot come cheap for full satisfaction. Intel & Asus motherboards could be the most famous worldwide (definitely so in Asia). A near similar question found in "Which motherboard is best for graphics software?" with an expert advice, check it. It all comes down to the use one intends to put it to.
10 motherboards
If you mean "how many models of motherboards" - thousands. If you mean "how many pieces of motherboards" - probably billions.
See the Related Link below for pictures of motherboards.
All Intel chipsets and motherboards support crossfire.
Motherboards are pretty much manufactured the world around. Most for PC's come from China, Taiwan, Korea, India, Japan, Malaysia and the such. Motherboards for US weapon systems are made in the US. Many European countries make motherboards.
Yes. Intel manufacturers both OEM and retail desktop motherboards.
MSI motherboards are a good choice for replacement motherboards for your desktop. Few people have any problems with them and they have an average rating of over four stars on Amazon.
Motherboards are the main Printed Circuit Boards inside a computer, they hold most of the important parts of the computer.
Most Pci-express x16 2.0 compatible motherboards
You can look for good deals in laptop motherboards at electronic stores such as Best Buy and Future Shop. You can also find laptop motherboards at online shopping sites such as eBay.
Hundreds of motherboards are compatible with DDR SDRAM. It would be impossible to provide a comprehensive list.