Its not needed but recommended for better use.
No. If you want dual CPUs from AMD, you need to get opteron CPUs.
Yes, the AMD Phenom II X4 955 is a quad core processor meaning that this processor has four cores or CPUs.
Turion
Yes, It is compatible.
No, you need to change your motherboard if you want an amd Processor. I'd suggest you'd go for an intel i7 980x
You can use an amd sempron or an amd athlon II with an am3 socket, but when am3 was released it was meant to be used with the amd phenom line of CPUs. You can use all three: amd sempron, amd athlon II & amd phenom.
The AMD Phenom series of CPUs is AMDs QUAD-CORE series of CPUs and are available at a start of around $200+ sold seperately. Only some of the most advanced motherboards of todays era of computers (march '09) are compatible with these processors. Please look up your motherboard's model number and refer to the company's website to confirm its compatibility with the Phenom processor.
The AMD Phenom series of CPUs is AMDs QUAD-CORE series of CPUs and are available at a start of around $200+ sold seperately. Only some of the most advanced motherboards of todays era of computers (march '09) are compatible with these processors. Please look up your motherboard's model number and refer to the company's website to confirm its compatibility with the Phenom processor.
No, the i7 is a very fast processor and even to keep up, you would need something like an AMD Phenom 8-core.
Processors are generally exchangable, as long as(!) the motherboard support the other processor, both with socket and BIOS compatibility. so probably no you cannot if your running a sempron. unless you are running it on a sweet motherboard and just upgrading from a bare bone setup which i take you are probably not.
no, the motherboard has the fm2+ socket while the cpu is a am3
No, it is not possible to substitute an AMD processor for an Intel processor on the same motherboard. The two processors use different types of mounting sockets, so they are incompatible. It would be akin to trying to put an alternator from a Ford into a Toyota. If you want to move to AMD, you would need to replace both the processor and the motherboard, possibly the RAM as well (depending on whether the new motherboard uses the same speed and type of RAM as the old motherboard).