Few questions about motherboard compatibilities

[chinesekidx]

I have a few questions about motherboards. When a motherboard lists the CPU Types on it's specification, but your CPU is not listed there, is it still compatible with the CPU Socket Types that the motherboard can support? (for example: a motherboard can support AM3 CPU Socket Type processors, but the brand/name of your CPU is not listed on the type of CPUs it can support, would it still be compatible with the motherboard?)

Another example. Lets say I had this motherboard:
Newegg.com - BIOSTAR A770E AM3/AM2+/AM2 AMD 770 ATX AMD Motherboard
And the CPU I had was a Athlon II x3 AM3 socket. Would it still be compatible even though it wasn't listed on its CPU Types?

I have another question related to RAM support for motherboards. Lets say a motherboard supports only ddr2 ram chips. It lists ddr2 800 as its only memory standard. Would that motherboard still be able to support ddr2 1066 ram chips or ram chips that have lower MHz than 800(ddr2 667,533,etc)?

[RicheemxX]

Generally speaking you are much better of checking directly with the manuf's site rather than looking at retailers only specs. In this case of the Biostar board listed Biostar has a full cpu support list. Most, not all, manufs keep a running list of CPU's that a particular board will run.

In many cases with older boards, such as the one listed even if the CPU is supported with the socket the board still might need a bios update to run the newer chips. So its really hit and miss and there is no def. answer.

In other cases such as older socket 775 boards, even thought its the same socket the boards themselves simply weren't built to support some of the new socket 775 cpus. so no they wouldn't run some of the newer chips.

For RAM generally speaking a board can support RAM with faster and or slow speeds, the difference being with faster RAM it should clock down to whatever speed the board runs. So say your board supports DDR2 800 and you add that DDR2 1066 the board will clock it down the standard 800 speed.

[chinesekidx]

I see. Thanks for the heads up.

[chinesekidx]

Wait so what if you're using a RAM chip that's lower than the standard speed listed on the motherboard? Would it stay at that speed or would it be incompatible? Like if the motherboard supports DDR2 800 and you decide to use a DDR2 533 chip. Would the speed stay 533 or would it be incompatible?

[RicheemxX]

Almost all boards will support slower ram speeds, I've never heard of a board that only supports one speed no matter what! Faster speeds however are not always going to be supported, so as mentioned most the time the board will just clock down the RAM to a speed it does support.