CHAINTECH V915P, Справочное руководство

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active PCI device has to complete its transactions within 32 clock cycles
or hand it over to the next PCI device. For better PCI performance, a
longer latency should be used. Try increasing it to
64 cycles or even 128
cycles . The optimal value for every system is different. You should
benchmark your PCI cards' performance after each change to determine
the optimal PCI latency time for your system. Please note that a longer
PCI latency isn't necessarily better. A long latency can also reduce
performance as the other PCI devices queuing up may be stalled for too
long. This is especially true with systems with many PCI devices or PCI
devices that continuously write short bursts of data to the PCI bus. Such
systems would work better with shorter PCI latencies as they allow rapid
access to the PCI bus. In addition, some time-critical PCI devices may not
agree with a long latency. Such devices require priority access to the PCI
bus which may not be possible if the PCI bus is held up by another device
for a long period. In such cases, it is recommended that you keep to the
default PCI latency of
32 cycles .
PCI SLOT1-3
This item allows you to select an IRQ address for PCI slot 1-3.
Options: Auto (default)
、
3
、
4
、
5
、
7
、
9
、
10
、
11
、
12
、
14
、
15
PCI Express relative items
Maximum Payload Size
This item allows you to set the PCI Express Maximum payload size per
time.
Options: 4096 (default)
、
128
、
256
、
512
、
1024
、
2048
Frequency/Voltage Control
Spread Spectrum
The spikes generated by your motherboards clock generator create EMI
(Electromagnetic Interference). This function reduces the EMI by
modulating the pulses so that the spikes of the pulses are reduced and
hence gives reduced EMI. But this reduction can mean that some of your
time-critical devices such as SCSI devices can be affected and their
stability reduced.
Leave the setting disabled especially if you are
overclocking your system. If you find you have to try this use the smallest
% setting possible.