Buying a single PCIe x4 card vs 2x PCIe x2 cards in RAID 0? Which is Better?

So I'm upgrading the SSD storage of my P650SE.. Currently using the 7200rpm 1TB disk as storage, installed WIN 8.1 on it as well.

I would like to instead install the OS and all my programs on a 512GB SSD card at great read and write speeds of atleast 1GB/s. It looks like in terms of M.2, the Samsung XP941 512GB M.2 80mm PCIe x4 SSD dominates with a 1170MB/s read and 980MB/s write speed, but that price is bananas!

SAMSUNG XP941 Series MZHPU512HCGL-00000 M.2 512GB PCIe Gen2 5Gb/s up to 4 lanes MLC Internal Solid State Drive (SSD) - Newegg.com

My question is this, I read about RAID 0 configurations and that they can actually BOOST performance of ssd cards, according to this article:

Feed your greed for speed by installing SSDs in RAID 0 | PCWorld

Is this true? And if it is, would it be fair to say that I would be able to buy 2 cheaper cards, set them up in RAID 0, and save myself $60 bucks while maintaining similar speeds? Also what is the limit of SSD storage? Can I theoretically install 2x PCIe x2 m.2 cards in those slots for over a TB of space or is there a cap limit?



Samsung XP941 512GB M.2 80mm PCIe x4 SSD (1 card)
1170MB/s read and 980MB/s write

Avg. Price - $500 for a single card



Plextor M6e PX-G256M6e M.2 2280 256GB PCI-Express
770MB/s read and 550MB/s write - in RAID 0 = 1540MB/s read and 1100MB/s write

Plextor M6e PX-G256M6e M.2 2280 256GB PCI-Express 2.0 x2 Internal Solid State Drive (SSD) - Newegg.com

Avg. Price - $219 for a single card - $439 for 2 cards in RAID 0

I know what you're probably thinking. "Dude its just $60 bucks man... Bite the bullet and just get the samsung card, stupid!" But those theoretical read and write speeds from the two plexors at a cheaper price seems very attractive! You guys have any thoughts on this? Have any of you had SSDS in RAID 0 before who can tell me if there are any performance increases? I'm interested to know and thanks for any responses on this!

 

if i remember correctly, the p650 only supports one pcie m.2 drive, no matter if its 2x or 4x. the only way to raid two m.2 drives would be if they both run in sata mode
thus, doubling current sata speeds would result in pretty much the same speeds as a single xp941 would reach, only that the latter wouldnt suffer from raid overhead and lack of redundancy / higher risk of data loss.
if it has to be either of these two choice id opt for the single xp941, but personally its not worth it just yet to upgrade to a m.2 drive, since 4k speeds are not really faster than regular 2.5" drives. ill wait for m.2 models maxxing out the pcie 4x connection first before i switch

 

Looked into that and you're right, it only uses one PCIe card or 2 x m.2 mSATA cards. And I've heard about 4k speeds, and tried looking into it, but I'm still confused on what they mean by it? Any links or description on what that's all about?

Also I'm not concerned too much with the RAID 0 data loss issue since I will be using the 1TB storage drive and my 2 other external drives as storage and backup! The SSDsd will be used purely for program installation for my Adobe programs and system applications. Also not concerned with 4k because, like their displays, they still have a lot of improvement to do!

A cool tool I used in calculating RAID that may provide useful:

RaidCalc - Raid Disk Space Utilization Calculator - Raid, RAID, Redundancy, Performance - iBeast Business Solutions

According to them, a 512GB setup would have 476.83GB of usable space. I think that's what you were getting at in terms of raid overhead? For a performance boost maybe it's worth it since that inaccessible 35.17GB is covered by the 1TB rpm storage drive.

That being said, In terms of M.2 mSATA amazon is selling 256GB sticks at $130 a pop.

http://www.amazon.com/dp/B00KLTPVV8

For $260 bucks... This is getting a little bit interesting! Will these cards work for this laptop though? Got my finger on the trigger for it, but hopefully you guys can confirm.

Also in terms of 4k, a single stick from transcend alone can support up to 75k IOPS vs the Samsung's 72k. I don't know if that number doubles in a RAID configuration, but perhaps that means something? I will say that read and write speeds of only around 560MB/s and 310MB/s is pretty pathetic, even doubled up at around 1120MB/s and 620MB/s when you consider the 1170MB/s and 980MB/s read and write speed of the samsung. Then again, for almost half the cost..


I also saw this one by CRUCIAL but I'm kind of confused if it will fit in the slots of the laptop....

http://www.amazon.com/Crucial-256GB...=1418591825&sr=1-5&keywords=crucial+m.2+256GB

The "M.2" confuses me, since they say that it also means "mSATA". Will that mean that this card is compatible then? It doesn't look like it..

 

Avoid half-baked (pun intended ) m.2 garbage for now, unless you enjoy having a portable mini stove inside your laptop.

What's worse is that it's the controller and not the NAND chips which is getting crazy hot. If that thing dies it'll just quit on you suddenly with absolutely no warning, and data recovery will be a very expensive venture.

 

phsew, lots of points for me to cover....alright here goes:

- M.2 and mSATA are two different connection types, not to be confused with one another! there is the regular SATA for 2.5" drives, theres mSATA which is NOT supported on the P650 (only on older models like the P150 series) and then there is M.2 which is capable to support either SATA mode or PCIe mode in 2x or 4x speed.

- by "4K" performance I am talking about the speed of a drive when it comes to reading and writing file sizes of 4KB, since that is the target size mostly used in a daily operation of a windows based system. sequential speeds are only important for the transfer of large file sizes, such as videos, image files, large zip or maybe iso files. otherwise, sequential speeds are pretty unimportant in everyday system operation and are only used by the PR / marketing branches of manufacturers in order to promote their drives. thus, the best storage drive out there is measured by its performance when reading and writing 4KB file sizes as opposed to sequential transfer speeds! Looking at the XP941 4K performance, it goes up to 122.000 IOPS Read and 72.000 IOPS writes. Compare that, for example, with an equivalent sized 850 Pro at 100.000 IOPS read and 90.000 IOPS write and ull see that there really isnt that much of a difference between the two!

- as for RAID overhead, I wasnt talking about storage space but rather performance of a RAID setup. It takes some processing power for the system to organize and handle a RAID configuration and properly divide all the data onto the striped / raided drives. thus, u will firstly never get exactly twice the performance of a single drive but rather a bit lower than that. also, when it comes to 4K performance numbers and access times, a RAID setup is actually a bit slower than a single drive. Thus, a RAID 0 setup will actually only significantly improve your sequential performance, but not the actually important stuff, namely the 4K speeds!

- the transcend drive uve linked is M.2 2280 and thus will work in your machine, as opposed to the crucial drive which is clearly mSATA and will thus NOT work in the P650. again, please be careful when choosing such a compact SSD, only buy M.2 drives and NOT SATA ones! and when choosing M.2, you will have to check if it works in SATA mode, in PCIe 2x mode or PCIe 4x mode. the only PCIe 4x drive out there atm is the XP941 btw.

- as for heat issues, n=1 is correct: if u choose to go with the XP941, make sure that u apply some kind of thermal pad onto it in order to keep this quite hot drive under control!

Cheers

 

Gah! I knew it was too good to be true! I did have some unbranded thermal pads that came with the laptop, but I don't know how effective they would be against the heated SSDs.

Makes a lot more sense now.

Been reading this article about those exact card I've mentioned in my original post.

http://www.pugetsystems.com/labs/articles/Samsung-XP941-Plextor-PX-G256-M6e-M-2-Qualification-575/

It looks like the plextor works better in terms of heating problems and compatibility with booting, but a remedy as of now (temporary) is getting a heatsink or slapping some thermal pads on it. Either way, it's a shame that they spent all that time on building small SSDs and forgot about something so trivial... Heat + Components = Big no no!

 

which model do u have, SG or SE? in case of the SE you could use thermal pads in order to connect the drive thermally with your aluminum backplate and thus use it as a giant heatsink, should work quite well

 

Plextor drives I swear beyond the sunlight are faster than samsung drives. If you find they have no heating issues, then I highly recommend them for their speed/reliability. They're just more expensive than samsung's drives, and I believe are all TLC and not MLC. Blah I'm too tired to sing plextor's praises and give their downsides this morning. They're just nice drives. Night *ninja sleep*

He said he has the SE in the first post

 

my bad, was zoning out there for a moment

 

Go with the single fast PCI-E, it's more likely to be useful in the future IF the capacity is enough for you.

 

UPDATE!

Bit the bullet and decided to just get the 2x256 cards from Transcend since I didn't have enough to buy that samsung card. I know I know, JUDGE ME!

Both cards work in the slots and I can set them up in RAID 0 configuration via the windows drive partition window.. However one problem. It makes them dynamic disks! They start out as basic unallocated drives so is there a way to RAID them up without making it dynamic? Essentially if they're dynamic, I can't install the OS onto it.

I read about doing this in the RAID Bios menu (setting bios boot from ACHI to RAID, rebooting, and pressing Ctrl + I), but the Raid bios window never starts up and it just BSODS. Any help on this?

 

Some bios have the raid controls in them, but you do have to make some changes to the registry to swap between AHCI and RAID mode.

 

Did what Meaker said and got it setup in RAID finally! Took some back and fourth between setting the Sata configuration to RAID in the BIOS then back to AHCI to boot the OS onto it. And now... the speeds!



Compared to my previous 7200 1TB drive.



It's slower than the best I am aware, but for $300 cheaper, its not bad I suppose. GLOOOORIOUS.

 

Single plextor SSD master race (somehow even beats your 4K read/write)


and this pitiful Samsung. I KNEW THE PLEXTOR WAS FASTER THAN YOU


Also, for giggles, my HDD

 

thats exactly the thing i was talking about when looking at the 4K speeds: the raid overhead causes two ssds to actually be SLOWER than a single drive in small file performance, and thats the actually important thing in everyday usage, sequential performance not so much...

 

Your single card setup is not too bad! I personally LOVE plextor! Is this after TRIMMING?

Very true! I can't believe how horridly slow the 4k is! So I looked into it and tried enabling the write cache on the RAID as well as TRIMMed the setup.



Noticed that my 4k read and sequential read, was actually WORSE by a few MBs or so, with an increase to all write speeds (except 4k QD32) and 4K writes of 237%. That's a little better I suppose!

 

If TRIMMING is something I am supposed to manually do, I have never done it.

 

If you have windows, you can set it up by opening Defrag & optimize (or defrag) and selecting your SSD. If it detects it as a solid state drive, you can hit optimize which will tell windows to TRIM. Make sure it says solid state and not Hard Disk, otherwise you'll make it defrag, which will ruin your card!

 

You don't have to manually TRIM but you can, using technique Xavvy showed.

 

Trimmed it; it improved VERY slightly in a couple aspects (Samsung) but for the most part it still sucks compared to the Plextor. #PlextorMasterRace