Motherboard bus speed and DDR Ram speed

[Beamer]

I have a laptop with FSB speed mentioned as 400Mz but the RAM as DDR2
533 memory.
My question is , How can a system with 400Mhz FSB support the 533Mhz
RAM? Does that mean the RAM is actually faster than the system bus.
Processor is P4 1.73Ghz centrino.

Please answer.

 

[George Macdonald]

I have a laptop with FSB speed mentioned as 400Mz but the RAM as DDR2
533 memory.
My question is , How can a system with 400Mhz FSB support the 533Mhz
RAM? Does that mean the RAM is actually faster than the system bus.
Processor is P4 1.73Ghz centrino.

Huh? "P4 centrino"? Don't think so - I think you mean Pentium-M Centrino.
It works because the memory channel is not clock-locked with the FSB and
the chipset has buffers which buffer data in and reclock it on the way out
- most chipsets have been able to do this for a long while now. Having the
memory clocked faster might, in theory, have some advantage when both CPU
and GPU are making requests for data from main memory... probably nothing
you'd notice.

 

[Tony Hill]

I have a laptop with FSB speed mentioned as 400Mz but the RAM as DDR2
533 memory.
My question is , How can a system with 400Mhz FSB support the 533Mhz
RAM? Does that mean the RAM is actually faster than the system bus.

It might. The memory bus and the processor bus are at least
semi-independent of one another.

Processor is P4 1.73Ghz centrino.

Umm.. there ain't no such thing! "Centrino" is a marketing term that
Intel uses to sell their processors, chipsets and WiFi chips as a
bundle. One of the requirements to get this "Centrino" branding, and
the associated marketing money from Intel, is the use of a Pentium M
chip. If you're system has a P4 processor than it's not a "Centrino"
system.

What you likely have as a processor is a 1.73GHz Pentium M chip, which
is a MUCH better notebook chip than any P4. However it's important to
note that this chip is designed to run with a 533MT/s bus speed, not
400MT/s.