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大家好..
狂少今天要來跟大家討論DDR ram的一些比較學術性的東西: DQS
有些東西真的很難用中文去翻 ;oplc;
大家忍著點只好理論和實測下去比較 ;oq;
以下是狂少所讀的有關DQS Strobe timing的特性簡述!
The DQS signal has several characteristics:
DQS is bi-directional
A DQS line is typically generated for 8 lanes of data from the DDR memory
The phase of DQS relative to the data depends on the operation being performed (Write or Read)
DQS is not free running
In the memory device, DQS is generated by DLL to minimize the skew between it and data
DQS has a Preamble state just after the signal comes out of tristate where DQS goes low
DQS has a Postamble state just before returning to tristate where DQS goes low
所以依以上特性來看,如果Read Preamble 設比較緊,然後要系統穩定的話
DQS Skew mode就要設Slower(慢一點)--->在A64tweaker的設定
在DFI NF4系列的BIOS內slower是increase(增加)
那DQS skew則設成128~192會有不錯的效果
從底下的測試我們可以看出一些端倪
以super pi 8m下去做比較:
測試環境:
CPU : AMD FX55, Mach II cooled
Mainboard: DFI NF4 SLI-DR (BIOS 310)
OS: Windows xp
Ram: GSkill 1gb LE DC Kit
Video card: X850xtpe, Water cooled
PSU: OCZ power stream 600adj
**注意,在BIOS調increase,在A64tweaker會變slower
decrease在A64tweaker會變faster
開始我們來看把DQS off的情況:
再來是開DQS slower(BIOS是increase的設定), skew調128,很明顯比off還快
最後是開DQS faster(BIOS是dcrease的設定), skew調128,很明顯卻比off慢(edit)
從以上結果,我們可以看到,開DQS不管是slow或fast的設定都會使效能增加強進而不失系統之穩定!雖然說差異是微乎其微,但是穩定度真的有差哦.
狂少今天要來跟大家討論DDR ram的一些比較學術性的東西: DQS
有些東西真的很難用中文去翻 ;oplc;
大家忍著點只好理論和實測下去比較 ;oq;
以下是狂少所讀的有關DQS Strobe timing的特性簡述!
The DQS signal has several characteristics:
DQS is bi-directional
A DQS line is typically generated for 8 lanes of data from the DDR memory
The phase of DQS relative to the data depends on the operation being performed (Write or Read)
DQS is not free running
In the memory device, DQS is generated by DLL to minimize the skew between it and data
DQS has a Preamble state just after the signal comes out of tristate where DQS goes low
DQS has a Postamble state just before returning to tristate where DQS goes low
所以依以上特性來看,如果Read Preamble 設比較緊,然後要系統穩定的話
DQS Skew mode就要設Slower(慢一點)--->在A64tweaker的設定
在DFI NF4系列的BIOS內slower是increase(增加)
那DQS skew則設成128~192會有不錯的效果
從底下的測試我們可以看出一些端倪
以super pi 8m下去做比較:
測試環境:
CPU : AMD FX55, Mach II cooled
Mainboard: DFI NF4 SLI-DR (BIOS 310)
OS: Windows xp
Ram: GSkill 1gb LE DC Kit
Video card: X850xtpe, Water cooled
PSU: OCZ power stream 600adj
**注意,在BIOS調increase,在A64tweaker會變slower
decrease在A64tweaker會變faster
開始我們來看把DQS off的情況:
再來是開DQS slower(BIOS是increase的設定), skew調128,很明顯比off還快
最後是開DQS faster(BIOS是dcrease的設定), skew調128,很明顯卻比off慢(edit)
從以上結果,我們可以看到,開DQS不管是slow或fast的設定都會使效能增加強進而不失系統之穩定!雖然說差異是微乎其微,但是穩定度真的有差哦.
