Choosing an SSD - what to look for?

elivance

Distinguished
Jul 9, 2010
84
0
18,630
So the specs I've been looking at are sequential read/write speeds, but I have seen on the forums that random IOPS is more important? Most drives don't have this listed and it is hard for me to compare them. My motherboard has SATA III, but it looks like there are few options and they don't appear that much better...

This drive has 50,000 IOPS with 4k random write. Is that a good number or is that typical?

Mushkin Enhanced Callisto Deluxe MKNSSDCL120GB-DX 2.5" 120GB
http://www.newegg.com/Product/Product.aspx?Item=N82E16820226152

I'm in the market for one around 120-128GB. I want a good one obviously, but don't want to break the bank too much (Price range = $300-350). What do you guys recommend? Thanks!
 
Solution
About the only compare of SATAII vs Sata III SSDs:
http://www.anandtech.com/show/3812/the-ssd-diaries-crucials-realssd-c300

As you can see:
(1) While the Intel G2's are still great, they have been upstaged by SF controller.
(2) The Vortex 2 (SATA II) is not far behind the SATA3 SSD. To really take advantage of SATA III you would need to run them in a raid0 config (which currently does not allow win 7 Trim cmd to pass.
(3) the old cost/performance, If the "NEW" drive (normally has a higher price) is significantly higher than say a vortex 2 I would go with the Vortex 2, But thats your call.
(4) added: I would expect the some good sales for the Xmas shopper crowd but again that is not a given - just a very good chance...
Intel X25-M 80GB for $219.99, or 160GB for $469.99 here.

80GB will be plenty, because you'll want to keep a HDD for data/media and/or backups.

I don't know what IOPS are, but I check the read/write speed. Yes, Intel is a liitle slow on the write speeds, but once the OS is installed, READS IS WHERE IT'S AT!

Wait for a while to buy SATA III SSDs. Intel maybe coming out with theirs by X-mas. I mean don't buy a SATA III drive now, get a SATA II. Plenty fast!

 

mark_k

Distinguished
Dec 31, 2008
610
0
18,990


I am running an ASUS P6T Deluxe motherboard.
Does it support SATA III Drives.
I tried to look on the net but could not find any info.....

Thanks

Mark
 

gtvr

Distinguished
Jun 13, 2009
1,166
0
19,460
mark_k: http://promos.asus.com/US/eblast/asusX58z_slizone/P6TDel_Specs.pdf shows your board supports sata II (3.0Gb/s). Only boards in the past few months will support sata III (6.0Gb/s). That is very rarely an issue, anyways, as almost nothing takes advantage of those speeds. Today.

For the OP - IOPS (input/output ops per sec) - I've seen this number considered critical in things like databases, where you have many simultaneous things going on at all times. For home PCs, read/write speeds, and random access time (great on SSDs) are important. Take a look at some of the reviews on Toms and throughout the net.
 

elivance

Distinguished
Jul 9, 2010
84
0
18,630
I'll for sure keep a larger HDD for storage, but I'd like to have the space for several games.

One other thing I had read is that the controller for larger drives can read more places in the SSD at once, or something along those lines. Is this true? Will a larger drive be able to (in theory) read faster?

If I want to get a SATA III SSD in about 6 months, it probably isn't worth it to buy a SATA II SSD right now... and realistically, I'm going to wait at least 1-2 months anyway. So random access time and sequential read/write speeds are what matters? I'm starting to think I'm going to budget my new computer around the other parts for now, and just use a HDD for the next 6 months or whenever I can get a good SATA III drive.

But that leads to another question:
Does SATA III really matter? SATA II transfers at 3gb/s, SATA I transfers at 1.5gb/s. If the fastest SSDs can "only" read at <400 mb/s, why does it matter? The bottleneck is the drive either way, so will it really make any difference if you use SATA 1.5gb/s or 6gb/s?
That being said, the few available drives that utilize SATA III do have different read speeds listed for the different SATA speeds. Obviously it makes some difference, but how?

Basically my question is, how much better can I expect SSDs to be in the next 6 months?
 
About the only compare of SATAII vs Sata III SSDs:
http://www.anandtech.com/show/3812/the-ssd-diaries-crucials-realssd-c300

As you can see:
(1) While the Intel G2's are still great, they have been upstaged by SF controller.
(2) The Vortex 2 (SATA II) is not far behind the SATA3 SSD. To really take advantage of SATA III you would need to run them in a raid0 config (which currently does not allow win 7 Trim cmd to pass.
(3) the old cost/performance, If the "NEW" drive (normally has a higher price) is significantly higher than say a vortex 2 I would go with the Vortex 2, But thats your call.
(4) added: I would expect the some good sales for the Xmas shopper crowd but again that is not a given - just a very good chance. Also may see some for the "Back-to-school sales.

Yes, the larger size of the same drive generally has sligthly higher performance. Emphase on sligthly.
 
Solution
SATA II transfers at 3gb/s, SATA I transfers at 1.5gb/s. If the fastest SSDs can "only" read at <400 mb/s, why does it matter?

Well, 400MB/s is faster than 3.0Gbps. SSD drive scale in power of 10, so 400MB/s equates to 4.0Gbps.

MB/s= MegaBytes per second. Gbps=GigaBITS per second. So 100MB = 1Gb.

So that's why SATA III has come to surface. But I don't trust Marvell controllers yet, I DON'T like JMicron controllers. (These are onboard SATA III and SATA II chipset controllers respectively.) Can't wait until Intel comes out with a new chipset to support SATA III, and USB 3.0.

Anyone is welcome to correct me if I'm wrong!
 

elivance

Distinguished
Jul 9, 2010
84
0
18,630




Ah, I had confused the discrepency between bits/bytes. (I hate how they list speeds as bits/s...) This does make SATA III a more realistic option as SSDs come up in speed. The RAID SSD route would be cool, but it seems like TRIM is more important. Is RAID ever going to be supported by TRIM?

Thanks a lot for all of your help. I do think it is a good time to wait and see how things go. I don't want to get a SSD right before new technology takes hold - either prices will go down for current drives or I'll be able to get a better drive for the same money later. I lose either way if I purchase now, and I don't feel like its something I need quite yet. I'm very excited for the future of SSDs however.
 

elivance

Distinguished
Jul 9, 2010
84
0
18,630


It does look like random read is significantly better with the SATA III drives. Random write is about the same. I think this is something I'll want to utilize. The Crucial c300 is about $70 more than other brands' 128gb models.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820148348&cm_re=crucial_c300-_-20-148-348-_-Product

however, as Intel and other manufacturers come into SATA III, the competition will undoubtedly make them cheaper and will increase their performance. I think your advice to wait is good.
 
gtvr is correct 8 bits = 1 byte, and if memory serves me, 2 bytes = 1 word. (powers of 2)

SATA III drives hopefull will improve.

PcVantage (Closer to real life diff)
128 gig C300 , On Sata III / 128 Gig C300 on Sata II / OCZ vortex - Sata II
17106 / 16615 / 17103 (Diff in the mud)

For other
4 K Random Reads - 83.8 / 78.8 / 57.9 (C300 SATA III Big winner, 45% faster than Vortex 2, BUT Very little effect 6% going to SATA III
4 K Random writes - 110.4 / 110 /164.9 Vortex2 SATA II big winner - 49% faster than C300 on Sata III

Seq read/writes - Reads First
275.4 / 225.9 /212 C300 Sata III - winner Sata II by 22 %, & 30% faster than Vortex2
134.9 / 131.1 / 215.2 For writes, Votex 2 (SATA II) beats C300 (SATA III) by 60%

For the C300 on Sata III, Only real improvement is in seq reads. For writes, the SATA II Vortex 2 wins hands down.

As in the BIG MAC - "Show me the Beef", so it goes in the speed contest, "Show me the Diff" in real life, not Benchies

Bear in Mind - Down stream There will be a real life diff, just not there yet (Not counting raid0 config)

Price - It has been, and always will be, demand vs availability ( good formula $=(unkF)*(d/a) Note: (unkF) = economy, buyers mood in general.