M.2 choice and power consumption

Insomniator

Diamond Member
Oct 23, 2002
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Got a new laptop (MSI GS43VR) and want to replace the stock 128GB m.2 SSD with a ~500GB model, while also removing the 2.5" 1 TB HDD.

I'm not a power user (gaming and movies) so I probably won't be going for a 960 PRO. In fact, the MX300 or Intel 600p look fine. I'm also considering waiting for the WD black m.2 to be released.

My main question is for example the AT review of the 600p states 'its not suitable' for notebooks due to its high power usage. Is that just 1% enthusiast talk or are we talking serious changes in battery life here? I'm currently testing the battery life playing an 1080p MKV on repeat... headed for about 7.5 hours of battery life with the stock SSD/HDD. If I throw a 'power hungry' intel 600p drive, are we talking an hour less? 5 minutes?

Thanks!
 

Billy Tallis

Senior member
Aug 4, 2015
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First things first, figure out whether you are looking for a M.2 SATA SSD, M.2 PCIe SSD, or if your machine can accommodate either.

PCIe power management is a minefield compared to SATA, and a multi-lane PCIe link fundamentally requires more power to operate. If you care about battery life, you should either play it safe and get a nice efficient SATA SSD like the MX300, or be prepared to go down the rabbit hole of configuring your system to ensure that PCIe ASPM and NVMe power states are actually used. But even if you ensure that you have optimal idle power savings, the PCIe SSD will be sacrificing efficiency for the sake of performance when you're actually using it. Consider the ATSB Light power results: The MX300s are using about 0.31-0.35 Wh for this test while the Intel 600p uses 0.79 Wh. The drives were transferring the exact same amount of data and the Intel 600p completed the test quicker, but it used more than twice the energy in that short span of time than the MX300s did.

The ATSB Light is a test that takes about half an hour to run, with the disk busy for less than 5 minutes of that time. The rest of the time is short idle periods of no more than 25ms. Ideally, in real world usage the SSD would be entering a low-power state after those short idle periods. In order to have a test that doesn't take all day (or all week for The Destroyer) we cut out the long idle periods where the power saving modes would be used and issue the next request to the SSD after the short wait. In order to estimate the total energy usage of your SSD, you can add the energy usage of the drive on one of the ATSB tests and an estimate of the energy used by the SSD in idle states over an accumulated several hours. Eg. if you used the 600p but didn't get PCIe ASPM working (ie. the situation our desktop testbed is in), you might have 0.79 Wh + 328 mW * 4 h = 2.1 Wh out of your battery's 61 Wh total (3.4%) going just to your SSD for ~4 hours of casual use. The MX300 would use something more like 0.5 Wh (0.8%) of your battery over the same time span and for the same usage. Over your longer battery life of about 7.5 hours, you're looking at a difference of about 15 minutes just due to idle power—assuming you never actually access the SSD. (NOTE: These are all rough estimates. There are several variables I haven't accounted for, and it is unlikely that all of my assumptions apply to your situation. I test SSDs in a desktop setting and don't have hard data about the effectiveness of SSD power savings in typical laptops.)

Either way, the SSD is not close to being the most power hungry component of your system. But your laptop appears to only have SATA connectivity to its M.2 slot, so it doesn't really matter. The Intel 600p isn't an option for you.
 
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Insomniator

Diamond Member
Oct 23, 2002
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Thanks for the detailed response! According to MSI, my laptop does have NVME X4 support. I'll have to do some more research and see how the WD Black does.
 

coercitiv

Diamond Member
Jan 24, 2014
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You might want to test removing the SATA HDD first, and make sure the system reacts properly without a drive present. (no storage related stutter, no extra CPU load)

Normally removing the disk should have no adverse effect on the system, but laptops are strange beasts with BIOS configs built with specific configurations in mind. For example, removing my SATA optical drive in an Asus Haswell laptop induced some strange stutter even with that SATA port disabled via BIOS. I actually had to connect and disconnect a drive several times to make sure I wasn't imagining things.
 

Oyeve

Lifer
Oct 18, 1999
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You have a very similar laptop to mine, Lenovo Y700 17" model. Came with a 128gb m.2 ssd and a 1tb spiiny drive. Firtst thing I did was remove the spinny hd as that would definately be a bottleneck, and put in a 1tb samsung evo850 ssd and just recently I replaced the 128gb m.2 ssd with an evo 850 500gb m.2 ssd. No issues on any front with removing any hds and such. And win 10 home 64bit installed and activated with no problems.