After figuring out that my power saving settings were holding back my SSD's 4k read speeds (post here), i decided to turn them off one at a time to try to figure out which ones were causing the performance drop.
Here's what i did:
Test setup information (skip this if you wish):
Testing Methodology:(optional information)
Here are the results:
Overall difference:
Here all power saving settings are on (C-States enabled, CE1 enabled, SpeedStep (EIST) enabled, Intel Turbo Boost enabled, Thermal Monitor enabled, Virtualization Technology enabled)
Here all of the power saving settings are turned OFF except for Thermal Monitor and Virtualization Technology. I don't think turning Thermal Monitoring off is really a good idea so i didn't bother to test it. As you can see, with every power saving setting turned off, there's a tremendous increase in 4k read speeds and a small increase for everything else. In fact, the 4k read speeds increased by 72% and the overall score improved by 7%! So this tells me that at least one of these settings is hindering SSD performance, so i tested each setting individually below.
Individual results:
Here all the power saving settings are on except CE1 is disabled. Turning off just CE1 increased 4k read speeds by nearly 15%.
Here all power saving settings are on except C-states is disabled. I have a feeling this turns off CE1 too on my motherboard, it's a fairly common problem with Asus motherboards. Either way, turning off C-states leads to a huge 61% increase in 4k read speeds and an overall performance increase.
Just to be sure, i tried disabled CE1 along with C-states at the same time to see the difference. The test results here are quite similar to the one above so i have a feeling when i disable C-States but leave CE1 on that CE1 is actually being disabled too. The reason i say this is because there seems to be a huge variance in 4k write speeds with AS SSD and besides that one test, everything else was nearly the same as when i had just C-states off.
Here all power saving settings are on except Intel Turbo Boost. Even though turning off Turbo Boost increased 4k read speeds, it decreased 4k-64Thrd read speeds and reduced 4k write speeds (though i think the write speeds are just because of AS SSD inaccuracy in that test). This decrease might be because the AS SSD benchmark is being bottlenecked by the CPU.
Here all power saving settings are on except Intel Turbo Boost and SpeedStep (EIST). Unfortunately, i wasn't able to turn just EIST off without also turning off Turbo Boost. Overall performance increased compared to when just Turbo was turned off. Interestingly, the 4k read times are lower with EIST off compared to when just Turbo was turned off. Compared to the test with all the settings turned on, turning EIST and Turbo off had little to no effect.
Here all power saving settings are on except i turned Virtualization Technology off. I know it's not a power saving feature, but i was curious if it would lead to a performance increase. Sure enough it did, it lead to a ~12% increase in 4k-64Thrd read speeds.
Overclocked Results:
Here i overclocked the CPU to 3.7ghz with all power saving settings turned off (Thermal Monitor and Virtualization Technology are still on). If you compare this to the stock test i did above with all the settings off, you can see there's actually a minor improvement across the board with a fairly substantial increase in 4k read speeds.
Here i overclocked the CPU to 3.7ghz with all power saving settings turned on except turbo boost. i didn't have time to test each setting individually while the cpu was overclocked as it would take an enormous amount of time to get things stable after each change. I also don't think having turbo boost off will effect much as the cpu is overclocked anyways. When compared to the stock results above with all power saving settings on, there was a small decrease in 4k write speeds. Again though, i don't know how accurate AS SSD is with 4k write speeds as they have been all over the place in each test. Other than the 4k write speed decrease, everything else is about the same. After seeing the results from the overclocked test with all setting turned off, it's hard to draw a conclusion here. Maybe overclocking only leads to a performance increase when all power saving settings are off?
Overall conclusion:
By turning off all the power saving features, i saw a 72% increase in 4k read speeds and a 7% increase in the overall score. Turning off just CE1 led to a 15% increase in 4k read speeds, turning off just C-states (and presumably CE1 too) led to a 61% increase in 4k read speeds, turning off just Turbo Boost led to a 15% increase in 4k read speeds (though the overall performance declined, most likely because the SSD benchmark was being bottle-necked by the CPU), turning off just Turbo Boost and EIST led to a 3% increase in overall performance although 4k read speeds remained unchanged (not sure what to make of this since turning off turbo boost above lead to an increase in 4k read speeds but not here), and turning off just Virtualization led to a 12% increase in 4k-64Thrd read speeds . Lastly, overclocking the CPU to 3.7ghz when all power saving features were off led to a 3% increase in 4k read speeds and a 2.5% increase in the overall score.
Keep in mind, what i observed might not be the case with other CPU's, other motherboards, and other SSD's. But i strongly suggest that everyone test their SSD speeds with all of these features turned off for him or herself to see if they see an increase in performance.
Here's what i did:
Test setup information (skip this if you wish):
System setup:
Crucial M4 256GB connected via SATA2
ASUS P7P55D Deluxe
Intel Core i5-750 @ default clocks unless otherwise mentioned
G.SKILL Ripjaws Series 4GB (2 x 2GB)
EVGA GeForce 8800 GTS 320MB
Software/drivers:
All system drivers, motherboard bios, and SSD firmware are up-to-date
AS SSD Version 1.6.4237.30508 was used for all tests with default settings
Using a fresh instal of Windows 7 64 bit with no additional programs except firefox and various benchmarks
SSD setup:
Flashed to newest Firmware version before windows install
Windows installed with the bios set to AHCI before windows install
Aligned to 4096K before windows install
Compression is turned off
Indexing is turned off
Power options are set to High Performance with both harddrive options set to 'never'
TRIM is enabled
Write Caching is enabled
Write-caching Buffer Flushing is disabled
Prefetch and Superfetch are both enabled (i forgot to disable these, it shouldn't change anything in this test though)
Crucial M4 256GB connected via SATA2
ASUS P7P55D Deluxe
Intel Core i5-750 @ default clocks unless otherwise mentioned
G.SKILL Ripjaws Series 4GB (2 x 2GB)
EVGA GeForce 8800 GTS 320MB
Software/drivers:
All system drivers, motherboard bios, and SSD firmware are up-to-date
AS SSD Version 1.6.4237.30508 was used for all tests with default settings
Using a fresh instal of Windows 7 64 bit with no additional programs except firefox and various benchmarks
SSD setup:
Flashed to newest Firmware version before windows install
Windows installed with the bios set to AHCI before windows install
Aligned to 4096K before windows install
Compression is turned off
Indexing is turned off
Power options are set to High Performance with both harddrive options set to 'never'
TRIM is enabled
Write Caching is enabled
Write-caching Buffer Flushing is disabled
Prefetch and Superfetch are both enabled (i forgot to disable these, it shouldn't change anything in this test though)
Testing Methodology:(optional information)
- The computer was reset before each new test (Obviously because i had to change bios settings
)
![tongue.gif]( "tongue.gif")
- Booted into windows
- Waited one minute before opening AS SSD
- Waited 1 additional minute after opening AS SSD to make sure everything was fully initialized
- Opened Windows Resource Monitor and made sure Harddrive and CPU activity was at 0-1% (idle system load) and that nothing other than 'System' was active under Disk Activity
- Closed Windows Resource Monitor to prevent logging writes during the test
- Ran AS SSD
Here are the results:
Overall difference:
Here all power saving settings are on (C-States enabled, CE1 enabled, SpeedStep (EIST) enabled, Intel Turbo Boost enabled, Thermal Monitor enabled, Virtualization Technology enabled)
Here all of the power saving settings are turned OFF except for Thermal Monitor and Virtualization Technology. I don't think turning Thermal Monitoring off is really a good idea so i didn't bother to test it. As you can see, with every power saving setting turned off, there's a tremendous increase in 4k read speeds and a small increase for everything else. In fact, the 4k read speeds increased by 72% and the overall score improved by 7%! So this tells me that at least one of these settings is hindering SSD performance, so i tested each setting individually below.
Individual results:
Here all the power saving settings are on except CE1 is disabled. Turning off just CE1 increased 4k read speeds by nearly 15%.
Here all power saving settings are on except C-states is disabled. I have a feeling this turns off CE1 too on my motherboard, it's a fairly common problem with Asus motherboards. Either way, turning off C-states leads to a huge 61% increase in 4k read speeds and an overall performance increase.
Just to be sure, i tried disabled CE1 along with C-states at the same time to see the difference. The test results here are quite similar to the one above so i have a feeling when i disable C-States but leave CE1 on that CE1 is actually being disabled too. The reason i say this is because there seems to be a huge variance in 4k write speeds with AS SSD and besides that one test, everything else was nearly the same as when i had just C-states off.
Here all power saving settings are on except Intel Turbo Boost. Even though turning off Turbo Boost increased 4k read speeds, it decreased 4k-64Thrd read speeds and reduced 4k write speeds (though i think the write speeds are just because of AS SSD inaccuracy in that test). This decrease might be because the AS SSD benchmark is being bottlenecked by the CPU.
Here all power saving settings are on except Intel Turbo Boost and SpeedStep (EIST). Unfortunately, i wasn't able to turn just EIST off without also turning off Turbo Boost. Overall performance increased compared to when just Turbo was turned off. Interestingly, the 4k read times are lower with EIST off compared to when just Turbo was turned off. Compared to the test with all the settings turned on, turning EIST and Turbo off had little to no effect.
Here all power saving settings are on except i turned Virtualization Technology off. I know it's not a power saving feature, but i was curious if it would lead to a performance increase. Sure enough it did, it lead to a ~12% increase in 4k-64Thrd read speeds.
Overclocked Results:
Here i overclocked the CPU to 3.7ghz with all power saving settings turned off (Thermal Monitor and Virtualization Technology are still on). If you compare this to the stock test i did above with all the settings off, you can see there's actually a minor improvement across the board with a fairly substantial increase in 4k read speeds.
Here i overclocked the CPU to 3.7ghz with all power saving settings turned on except turbo boost. i didn't have time to test each setting individually while the cpu was overclocked as it would take an enormous amount of time to get things stable after each change. I also don't think having turbo boost off will effect much as the cpu is overclocked anyways. When compared to the stock results above with all power saving settings on, there was a small decrease in 4k write speeds. Again though, i don't know how accurate AS SSD is with 4k write speeds as they have been all over the place in each test. Other than the 4k write speed decrease, everything else is about the same. After seeing the results from the overclocked test with all setting turned off, it's hard to draw a conclusion here. Maybe overclocking only leads to a performance increase when all power saving settings are off?
Overall conclusion:
By turning off all the power saving features, i saw a 72% increase in 4k read speeds and a 7% increase in the overall score. Turning off just CE1 led to a 15% increase in 4k read speeds, turning off just C-states (and presumably CE1 too) led to a 61% increase in 4k read speeds, turning off just Turbo Boost led to a 15% increase in 4k read speeds (though the overall performance declined, most likely because the SSD benchmark was being bottle-necked by the CPU), turning off just Turbo Boost and EIST led to a 3% increase in overall performance although 4k read speeds remained unchanged (not sure what to make of this since turning off turbo boost above lead to an increase in 4k read speeds but not here), and turning off just Virtualization led to a 12% increase in 4k-64Thrd read speeds . Lastly, overclocking the CPU to 3.7ghz when all power saving features were off led to a 3% increase in 4k read speeds and a 2.5% increase in the overall score.
Keep in mind, what i observed might not be the case with other CPU's, other motherboards, and other SSD's. But i strongly suggest that everyone test their SSD speeds with all of these features turned off for him or herself to see if they see an increase in performance.
