Can the FSB ratio create a bottleneck?

Asus P7p55d deluxe motherboard
September 8, 2010 at 20:44:51
Specs: Microsoft Windows 7 Home Premium, 2.891 GHz / 2045 MB
Simply stated: Does DDR3 1333 RAM, clocked @ native 1333 (fsb ratio = 1:1) acheive higher throughput than DDR3 1600 RAM with an overclocked fsb (fsb ratio = 5:1)?

Motherboard Name Asus P7P55D Deluxe

Front Side Bus Properties:
Bus Type Intel QPI
Real Clock 161 MHz
Effective Clock 161 MHz

Memory Bus Properties:
Bus Width 64-bit
DRAM:FSB Ratio 5:1
Real Clock 806 MHz (DDR)
Effective Clock 1611 MHz

See More: Can the FSB ratio create a bottleneck?

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September 8, 2010 at 22:20:49
There's is no fsb in core i series. Instead of fsb intel use qpi(quick path interconnect) for socket 1366, socket 1156 use DMI(digital media interface) previously used to make connection between nb & sb.
core i7 run dual channel at 1333ddr and triple channel at 1066ddr. If u do the math u will find ddr3 1066 (triple channel) has more bandwidth (20%) than ddr3 1333 (dual channel)
memory bandwidth=memory speed (ddr) x 64 /8
*Nothing gain running memory at 1600ddr*

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September 9, 2010 at 04:54:02
OK, I wondered why the report listed my bus type as QPI. I should have mentioned that I am running a socket 1156 board with Corsair Dominator XMP DDR3 1600 Dual-Channel memory. I let Asus BIOS use the XMP profile in the AI Tweaker and it chooses a BCLK of 160.

So for my case, given that I have to overclock the RAMDAC, would I be better off running the memory at 1333 (1:1) instead of 1600(5:1)?

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September 9, 2010 at 05:28:20
"Memory Bus Properties:
Bus Width 64-bit"
u are not running dual channel, 64bit is a single channel, 128bit is a dual channel, 192bit is a triple channel. Don't use AI TWEAKER, overclock manual.
Memory freq=base clock(default is 133mhz) x ram multiplier.
If u increase base clock ram freq increase, the only way to keep ram freq down is to decreas mem multiplier. There's other settings u need to set before oc.
list the system specs.

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Related Solutions

September 9, 2010 at 06:24:40
Since there is no FSB, there is no DRAM:FSB ratio to worry about.

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September 9, 2010 at 08:29:03
No worries... I like that - because this build, for a first build, went together far too easy and is exceeding all my expectations.

Easy as tinkertoys.

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September 9, 2010 at 08:31:59
These specs?

Asus P7P55D Deluxe
Intel i5-760 2.88 GHz
4 GB Corsair Dominator XMP (8-8-8-24)

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