whats the difference between cpu socket numbers?

[Solodays]

how is a cpu using socket 939 differ from a cpu using socket 750, 999 etc? are the higher number means better in moust occasions?

 

[n7]

I'll let the pros handle this one.

Too lazy to try to answer this well.

 

[DavidoFoo]

Different socket numbers denote a varying number of "pins" on said processors.

 

[midnight growler]

To really make it simple, its kinda like buying a new pair of shoes because the old pair doesn't fit anymore.

939 is the current AMD socket with all of the 64 bit and dual-core 64 found in 939 size (64+ 3000 to the newest 64X2 4800)
754 has some of the early 64 bit processors (3000 to 3700) as well as the older non 64 bit Sempron processors (2600 to 3300)

As for right now, go with the 939 socket if you're getting an AMD processor. It is the current size and you'll have plenty of time until you'll have to worry about the upcoming M2 socket (quite some time before its even released).

 

[elkinm]

I believe the biggest difference is that socket 939 has dual channel memory support and 754 is only single channel. I believe the extra pins are for the extra memory channel. As mentioned before 939 is more future proof with X2 support but I think 754 and 939 CPUs are identical otherwise.

 

[Bona Fide]

Higher doesn't necessarily mean better. The old FX line was 940 pins, but then they dropped one in the new series.

 

[Icepick]

There are different numbers of pins in these CPUs because they are built upon different architectures. AMD engineers decided that the architecture of the socket 939 CPU can be implemented the most efficiently with 939 pins. The biggest difference between a socket 939 CPU and a socket 754 CPU is that 939 can access memory in dual channel.

Higher CPU socket numbers (meaning more pins are used to connect the CPU to the motherboard) are NOT an indication of how robust the performance will be.

 

[Solodays]

what's memory dual channel?

 

[joex444]

Standard DDR and DDR2 is 64-bit wides at varying frequencies (MHz). When you multiply the width of the path (the connection from RAM to Northbridge, or in the AMD64 case, RAM to CPU) by the frequency of the path, you get the bandwidth of the path, and thus the actual theoretical bandwidth of the RAM. When you run dual channel, which uses 2 RAM sticks, the path changes to 128-bit. This doubles the bandwidth while keeping the RAM at the same speed. So, DDR400 (PC3200) has 3.2GB/sec of bandwidth (400*64/8 [bits to bytes]/1024 [mb to gb]), but in dual channel it's 400MHz * 128bits [/8/1024 bits to bytes, mb to gb] = 6.4GB/sec.