AMD CPU's & Hypertransport - explanation

[zero-one]

Hiya

I've finally got my head around how Intel CPUs work with the FSB and RAM. I'm still stuck with how AMD CPUs work with the Hypertransport and RAM. How is it all linked together? How is the RAM and CPU speed worked out?

Thanks

George

 

[theforce]

From my limited knowledge the memory controller is located on the motherboard (externally ) on systems that use Intel processors. AMD's memory controller is located inside the CPU which reduces the power consumption of your system from what i remember and in theory reduces the latency of data transferred from RAM to the CPU.
Hope this helps.

 

[FreeStream]

They are all basically the same. Just different words for the same thing.

FSB/HTT = base speed, EG 400MHz
Memory multi/divider = EG 1:1/100%/400Mhz = 400Mhz (DDR2-800)
CPU Multi = 9 = 400x9 = 3.6GHz

Hypertransport/Intels Quad Pumping is different in technology but nothing you have to worry about. Intel you can't change the multi of the quad pump its always 4x but with AMD you can change it, used to be 2-5x on 939 might be more now on AM2.

 

[zero-one]

Concorde Rules - you are a legend. That explains it perfectly.

 

[alexthecheese]

What I was wondering about the other day, is what is a clock multiplier? I know CPU speed = FSB x multiplier, but what exactly is the multiplier?

 

[TheMorningStar]

What I was wondering about the other day, is what is a clock multiplier? I know CPU speed = FSB x multiplier, but what exactly is the multiplier?

just a factory set multiplication of the bus speed to determin the cpu speed. generally ita all that seperates a £30 cpu from a £150 cpu...

 

[jaykay]

just a factory set multiplication of the bus speed to determin the cpu speed. generally ita all that seperates a £30 cpu from a £150 cpu...

How does it speed up the processors in the chip. Does it make the transistors open faster e.g 2.0ghz are slower than a 3.0ghz?

I've never understood how it makes the chip faster.

 

[FreeStream]

Concorde Rules - you are a legend. That explains it perfectly.

Vote for me for the poster of the year 2008 yea

lol - glad I could help

 

[mnemonix]

How does it speed up the processors in the chip. Does it make the transistors open faster e.g 2.0ghz are slower than a 3.0ghz?

I've never understood how it makes the chip faster.

Your pc components use a clock to determine what speed they run at and to synchronise communication with each other. The cpu speed results from this clock x the cpu multiplier.

 

[Amonlym]

the relationship between fsb and ram in intel systems: ram runs at fsb speed via a ratio: 2:3 1:1 3:2 etcetc

on amd the ram speed is a function of the cpu speed and the cpu multiplier: eg, X2 6000+
200*15 = 3000mhz, ddr400 ram runs at cpuspeed /15 = 200mhz(ddr = 400). 533 runs 3000/12 (as it must run at or below the selected speed) = 250mhz (ddr500) (and not 3000/11 = 272mhz > 266 and thus not used) 666 would run 3000/9 = 333.33, 800 @3000/8 = 375, 1066 @ 3000/6 = 500

change the multiplier for the X2 6400 (3200 - 16*200) and you now get 400=3200/16(200), 533=3200/12(266), 666= 3200/10 (320), 800 = 3200/8 (400), 1066 = 3200/6 = 533.33

to compair

Ram Speed (DDR) 6000+ 6400+
400 400 400
533 500 533
666 666 640
800 750 800
1066 1000 1066