What do you think is better? All ASUS motherboards that I have seen have it
to 32 by default but I have been reading in various review sites that the 64
setting is better for PCI bus utilisation. Anybody have any comments?
The PCI "Latency Timer" setting specifies how long the current bus master can
continue to use the bus after the arbiter has de asserted the current master's
GNT# (presumably in response to the assertion of another agent's REQ#).
Meaning (1) if there is no bus contention to begin with, the Latency Timer has
no function, and (2) if there is bus contention, all the LT does is enforce
fairness so no agent is totally starved.
You have to consider platform topology and where agents that can use more than
their nominally allowed bandwidth are located to predict the effects of
changing the LT. With graphics on its own bus, integrated disk, integrated
sound, and even integrated lan, there's precious little PCI arbitration going
on already, the contention is deeper in the topology than the periphery
represented by the PCI bus.
You can certainly change the value of the LT, and easily see the effects on
*benchmarks*, but in the end, measuring the real-use benefit is your
challenge.
/daytripper (Let us know how you make out ;-)
