Best SSD Group Test: Why should you buy an SSD?
SSDs are arguably the single best upgrade you can make to any PC or laptop. And now they're cheap enough that anyone can consider buying one.
There are numerous advantages to installing an SSD into your PC or laptop. A Windows installation on an SSD will boot in mere seconds rather than the minute or two it can take for an older, neglected hard disk to get ready for use, and applications installed to the SSD exhibit similarly rapid loading times – handy for both work and play.
SSDs can also be smaller than hard disks, which means they’re often able to fit where platter-based drives can’t reach. This makes them ideal for ultra-compact desktop PCs or of course the ever-slimming world of laptops. SSDs also have no moving parts, which makes them tougher and more reliable than traditional hard disks.
Best SSD Group Test: How We Tested
The six drives in this test have been subjected to a rigorous benchmark routine to weed out what’s worth buying and which can be left on the shelf.
Benchmark applications AS SSD and CrystalDiskMark run each drive through a variety of tests. Their sequential read and write routines test the raw file-copying pace of each drive, while a variety of random read and write tests demonstrate how responsive the drive is to the more random use a drive is put through during day to day use – the ‘snappy’ feel of an SSD is all about its random read access performance. ATTO’s benchmark also tests the read and write pace of each drive, but it uses an even larger variety of file sizes, which adds further detail to the picture of how each SSD will perform.
We’ve also run PCMark 7’s storage test, which uses simulations of typical file access patterns of real-world programs to give an indication of how each drive will handle real-world applications. We’ve also taken the temperature of each SSD – if any overheats it’ll be worth knowing, especially if it’ll be used in a confined space.
To help us decide which drive is this month’s best, we’ve lined up their prices and warranties – and taken a look at what extras you get in the box, too.
Best SSD Group Test: Under The Hood
The drives in this group cover a broad remit. The
Samsung 850 Pro and
SanDisk Extreme Pro are designed for high-end work machines and gaming systems, and the
Samsung 845DC products are intended for data centres and other intensive business applications. The
Crucial MX100 and
Intel 740 are mainstream drives intended for a broad range of PCs and laptops.
Samsung's latest SSDsSamsung has moved into a dominant position in the SSD market, and its 850 Pro follows on from the 840 Evo — the SSD that took home the top prize in our last test.
This flagship product has one big innovation: 3D V-NAND. This jazzy name describes a big change in the memory chips used inside this drive: as well as lining transistors up in a horizontal arrangement, the new 3D model layers them vertically, too.
This structure eases the squeeze on transistor size that’s caused electricity leaks, inefficiencies and higher costs in the quest for better performance. Now, Samsung can use larger, cheaper and more effective manufacturing processes without the squeeze on space – and it also means that more capacity can be fit into each chip.
The 850 Pro is the first consumer SSD to arrange NAND in this way, which clearly marks this drive out. However, that isn't the only big innovation in this drive — the triple-core MEX controller uses the same architecture as last year's model, but it’s clocked 100MHz faster, and the exterior looks identical, including the 7mm form factor.
The 850 Pro is available in capacities ranging from 128GB to 1TB, and we’ve tested the 512GB model that comes with 1GB of RAM. This drive will set you back £283, or 55p per gigabyte – only a penny more than its rivals.
SEE ALSO: GeForce GTX 750 Ti vs Radeon R7 265
The 850 Pro isn't the only Samsung drive in this group. The 845DC Evo is designed for more intensive business use, and it doesn't benefit from 3D V-NAND — instead, it’s built with 3-bit Toggle Mode TLC chips.
The choice of NAND is designed to improve the 845DC Evo's performance in two key areas: endurance and read-intensive workloads. It's available in 240GB, 480GB and 960GB capacities, adheres to the 7mm form factor, and follows the familiar Samsung aesthetic blueprint.
The 845DC Evo is partnered in the market by the 845DC Pro. It's another drive designed for hard work, but this time it's been built for write-heavy workloads, which means it's kitted out with the far longer lasting 2-bit MLC memory. We’ve tested the 480GB version of the Evo, and the 400GB Pro model.
Samsung hasn’t yet released pricing, as the 845DC drives won’t appear in the UK until next month, but US prices have begun to appear: the 480GB Evo will cost $490, which translates to £286.
Samsung has said that the Pro drive will cost between $1.50 and $2 per gigabyte: for our 400GB model that means prices between $600 and $800, which converts to a price between £350 and £467. That’s a large window, but there’s no doubt that it’ll be an expensive SSD.
Strong rivals from SanDisk, Crucial and Intel
Competition comes from the SanDisk Extreme Pro, which is designed for intensive workloads — whether they're in the office or in a gaming PC.
It's built using 19nm MLC NAND that's the same type of memory used inside Toshiba's fast drives, and it's been picked to provide a good mix of performance and consistency. That silicon is paired with a Marvell 88SS9187 controller. It's an old part – launched back in 2012 — but it's got a proven track record, and SanDisk has upped its game with custom firmware.
It's available in 240GB, 480GB and 960GB capacities, with 1GB of RAM available in the two larger SSDs and 512MB soldered into the 240GB version. We've tested the 480GB model that costs £257, or 54p per gigabyte – just one penny less than the Samsung 850 Pro.
SEE ALSO: Best Cheap Graphics Card Group Test
Intel’s entry in this group straddles the corporate and consumer worlds: the Intel 730 Series is an enterprise drive that’s now been unleashed for mainstream buyers. It’s controlled using the same chip that’s used inside Intel’s enterprise drives, but it’s been improved from 400MHz to 600MHz for the 730 Series.
The NAND chips are 20nm MLC, and the chips are clocked a bit higher than Intel’s older memory – 100MHz instead of 83MHz – and they’re bolstered with 1GB of RAM. You’ll pay £130 for this drive, which works out to 54p per gigabyte: the same as the SanDisk, and a little less than the Samsung.
All of those prices pale in comparison to the Crucial MX100. Our 256GB sample costs just £80, which works out at 31p per gigabyte – a stunningly low price that undercuts every other drive here.
The bargain-basement price means there's no room for Samsung-style sea-changes, but the MX100 still manages to innovate. It was the first mainstream drive to use 16nm NAND, which is the smallest process used since Toshiba and SanDisk introduced 19nm memory back in 2012.
It's a move that means more chips can be squeezed onto each slice of silicon, which means costs can be cut — and it also helps that the NAND inside this drive is manufactured by Micron, which owns Crucial.
Elsewhere, little has changed between this drive and the M550 that we tested in our last group, as the MX100 still uses the Marvell 88SS9189 controller — a step ahead of the SanDisk's chip on paper, but not far enough ahead to provide significant performance boosts. On the outside, it's business as usual: a slick silver 7mm chassis with a prominent blue sticker.
How long will they last?
It’s also worth looking at the rated endurance of all of these drives, especially if you’re going to be running lots of games or heavy workloads. The MX100 suffers here, as it’s only rated for 72TB – the smallest amount here, and less than half of the Samsung 850 Pro’s 150TB rating.
The SanDisk and Intel drives sit in the middle ground with endurance ratings of 80TB and 91TB, and the Samsung 845DC Evo displays its workstation credentials with a stunning 300TB rating. The 845DC Pro drive is classified in a different way – it’s designed for heavy write operations, and Samsung says it’s good for 10 full drive writes per day, which by our calculations works out as 7,300TB over the 5-year warranty the drive includes.
We’ve also mentioned two of the best drives from our last group test – the Crucial M550 256GB and the Samsung 840 Evo 250GB – as they’re still available. They’ve become tempting mid-range options, with the M550 costing £102 and the 840 Evo now retailing at £107.
Best SSD Group Test: AS SSD
AS SSD
|
|---|
READ |
Crucial 256
|
845DC Pro 400
|
845DC EVO 480
|
SanDisk 480
|
Samsung 840 PRO
|
Intel 730
|
Sequential |
519.52 |
518.83 |
510.72 |
519.22 |
522.29 |
518.4 |
4K |
38.43 |
31.74 |
33.54
|
33.1 |
33.58 |
35.39 |
4K-64 |
383.71 |
335.36 |
346.45 |
331.81 |
378.27 |
344.59 |
Access time |
0.037 |
0.032 |
0.037 |
0.04 |
0.04 |
0.029 |
WRITE |
|
|
|
|
|
|
Sequential |
497.87 |
330.9 |
435.17 |
438.78 |
486.49 |
473.12 |
4K |
121.38
|
123.76
|
109.59
|
105.86
|
120.32
|
107.6 |
4K-64 |
308.01 |
282.97 |
260.11 |
278.38 |
302.64 |
242.1 |
Access time |
0.026
|
0.043 |
0.03 |
0.037 |
0.044 |
0.028 |
In our last test five of the six drives returned sequential read scores of more than 500MB/s, but this time around performance has improved — all six new` drives hit at least 511MB/s. It's impressive, consistent pace that further illustrates the near-saturation of the SATA standard across the SSD market.
Top of our latest table was the SanDisk Extreme Pro, which hit 522MB/s. That's only two megabytes more than the Samsung 850 Pro and three ahead of the Samsung 845DC Evo, which has been produced with read performance in mind.
The Samsung 850 Pro took the lead in the sequential write test with a score of 498MB/s, with the SanDisk second best — albeit with a much slower time of 486MB/s – and the Intel drive in third. The two other Samsung drives returned middling pace around 50MB/s behind the two leaders, and the MX100 brought up the rear with a poor 331MB/s result.
The last generation’s two best drives weren’t far behind in this test, either. The Crucial M550’s sequential read and write scores of 517MB/s and 482MB/s (results not in table) are good enough to keep up with the faster drives here, and the latter score outpaces Crucial’s budget MX100 drive. The Samsung 840 Evo, meanwhile, fell behind most of the competition when reading but hit a respectable 483MB/s when writing sequential files.
The 850 Pro performed well when performing random reads of 4K and 4K-64 files with table-topping scores of 38MB/s and 384MB/s — in those tests, the SanDisk was 5MB/s and 6MB/s behind, with other drives further back.
The situation wasn't as clear-cut when writing these small files. The 850 Pro and SanDisk both fell to the surprising Crucial in the 4K test: the MX100's 124MB/s score was 3MB/s and 4MB/s ahead of its rivals. The 850 Pro regained its lead in the 4K-64 test, but its 308MB/s result was only 5MB/s beyond the SanDisk. Bottom of the table, surprisingly, was Intel: its 4K-64 write pace of 242MB/s was 18MB/s behind the next-best product.
The two older drives showed their age when handling small files. Crucial’s M550 was fantastic in our last test, but its results would have only been good enough for last place in three out of our four small file tests in the new group. The Samsung 840 Evo suffered similarly – even the £80 Crucial MX100 was faster in three of the four tests.
When it comes to AS SSD, the 850 Pro is the victor. It's the fastest drive in the majority of our tests and, when it's not in first place, it's never far behind — as close as 2MB/s in one test. The SanDisk is an impressive runner-up, and the other two Samsung drives did little to impress: they may specialise in reads and writes, but neither could match faster competitors in these areas.
Crucial’s drive impressed, considering its price – not far behind in some benchmarks, and also demonstrating a significant speed boost over the last generation of high-end drives in some tests.
Best SSD Group Test: CrystalDiskMark
CrystalDiskMark
|
|---|
READ |
Crucial 256
|
845DC Pro 400
|
845DC EVO 480
|
SanDisk 480
|
Samsung 840 PRO
|
Intel 730
|
Sequential |
545.4 |
509.3 |
487.6 |
536.5 |
536.3 |
472 |
512K |
433.1 |
464.1 |
405.6 |
447.9 |
336.8 |
413.6 |
4K |
42.34 |
34.65 |
38.05 |
36.08 |
36.4 |
39.71 |
4K-32 |
404 |
351.5 |
376.7 |
354.1 |
403.9 |
365.1 |
WRITE |
|
|
|
|
|
|
Sequential |
512.8 |
345.7 |
463.4 |
449.1 |
495.3 |
482.1 |
512K |
508.2 |
345.8 |
450.9 |
451.2 |
467.4 |
463.8 |
4K |
150.8 |
149.0 |
124.5 |
125.0 |
98.15 |
150.5 |
4K-32 |
355.8 |
325.7 |
337.7 |
329.1 |
351.9 |
347.9 |
The Samsung 850 Pro was strong in AS SSD's sequential tests, so it's no surprise it's done well here. It's the only drive in this group to go beyond 500MB/s in both read and write benchmarks, and its results of 545MB/s and 513MB/s easily outpace the SanDisk, which hit 536MB/s in the read test but 496MB/s when writing.
Samsung's 845DC Evo hit a decent 537MB/s in the read test but was let down by its write speed of 449MB/s, and the 845DC Pro reversed that pattern with better write performance. The budget MX100's read score of 509MB/s was fourth out of the five drives, but its write pace of 346MB/s is the worst here by a long way.
No drive took a convincing lead in the mid-sized 512KB benchmarks. The MX100's 464MB/s pace was the best when reading, but its 346MB/s write score propped up the results table. The 850 Pro topped the table with 508MB/s in the write test, but its 433MB/s read score was third-best - a rare mis-step for this drive. The SanDisk was the worst SSD here for 512KB reads, and the two Samsung 845DC drives were consistently mid-table.
CrystalDiskMark has two sets of 4K tests, and the 850 Pro dominated all four read and write tests. The closest challenger here was the SanDisk, with the MX100 proving the slowest across the quartet of read and write runs.
It's another great performance for the Samsung 850 Pro in CrystalDiskMark, and the margin of victory is greater: there are eight benchmarks in this portion of our test, and the 3D V-NAND inside the 850 Pro helped Samsung win seven of them.
The two older drives exhibited familiar performance patterns in CrystalDiskMark. Both the Crucial M550 and Samsung 840 Evo were able to keep up with new SSDs in some of the sequential read and write tests, but both drives showed their age when working with random transfers – most of the current crop were significantly quicker.
The SanDisk was frustratingly inconsistent, with great performances in some tests hampered by awful results in others, and the Intel 730 was similarly irritating: it showed consistently good speeds in the writing benchmarks, but it was let down by sluggish performance in the read tests. The Crucial MX100 was largely poor, with group-leading pace in one test unable to banish bottom of the table results in five other benchmarks.
Best SSD Group Test: Atto Disk Benchmark
Atto Disk Benchmark
|
|---|
READ |
Crucial 256
|
845DC Pro 400
|
845DC EVO 480
|
SanDisk 480
|
Samsung 840 PRO
|
Intel 730
|
8 |
438,421 |
186,533 |
414,941 |
325,779 |
462,045 |
328,134 |
32 |
533,963 |
361,977 |
509,448 |
482,527 |
535,298 |
426,951 |
64 |
551,875 |
427,932 |
489,080 |
512,507 |
550,502 |
482,233 |
256 |
559,078 |
548,890 |
537,863 |
551,402 |
534,285 |
544,127 |
1024 |
563,151 |
551,579 |
559,240 |
554,109 |
544,125 |
546,432 |
4096 |
563,151 |
551,579 |
560,538 |
556,663 |
522,502 |
547,827 |
8192 |
595,789 |
551,579 |
560,538 |
556,663 |
526,344 |
546,588 |
WRITE |
|
|
|
|
|
|
8 |
412,876 |
335,544 |
357,179 |
389,865 |
429,179 |
401,479 |
32 |
502,530 |
345,875 |
444,034 |
446,227 |
501,938 |
472,344 |
64 |
520,971 |
345,875 |
465,859 |
441,863 |
517,619 |
483,647 |
256 |
531,313 |
345,015 |
373,967 |
442,732 |
511,024 |
501,247 |
1024 |
532,874 |
346,368 |
484,759 |
440,058 |
519,971 |
503,994 |
4096 |
536,870 |
345,625 |
483,667 |
440,058 |
523,776 |
503,994 |
8192 |
534,495 |
346,368 |
481,498 |
442,128 |
473,014 |
503,994 |
This testing application delves deep into different file sizes to provide a more granular view of read and write performance.
For once, the 850 Pro didn't start in the lead - in the 8KB portion of this test, the SanDisk's 462MB/s reads and 429MB/s writes were the best here. The Extreme Pro stayed ahead of the Samsung when working with 32KB files, and there was little to choose between the two SSDs when reading and writing 64KB workloads, too.
By the time file sizes had increased to 256KB, though, the 850 Pro proved the better drive. In the larger file read tests it was the best drive here, and it maintained its lead in the larger file write tests. The Extreme Pro's inconsistency was its downfall; while it remained a close second in every large file writing test, its results hit rock bottom in the read benchmarks.
The 845DC Evo may be designed for read-heavy workloads, but it proved consistently mid-table in both read and write tests. We couldn't say the same for the write-intensive 845DC Pro, which hit second place in a couple of read tests but faltered in several read and write benchmarks.
The cheap Crucial MX100 was really exposed in this set of benchmarks. Our ATTO run comprises of fourteen tests, and it was bottom of the pile in ten of them - and only the SanDisk's inconsistent, poor large file read performance prevented that figure from being even worse. It’s also slower than the older but pricier Crucial M550.
The Intel drive followed on from CrystalDiskMark by solidifying a place in the top three SSDs when it came to writing files, but falling into the bottom half of the table when reading data. Samsung’s older 840 Evo, meanwhile, held up well: it matched more expensive products in some of the write tests, and wasn’t far behind in read benchmarks.
There’s no mistaking the winner here, though – the Samsung 850 Pro took the lead in twelve out of the fourteen tests.
Best SSD Group Test: IOMeter
IOMeter
|
|---|
|
Crucial 256
|
845DC Pro 400
|
845DC EVO 480
|
SanDisk 480
|
Samsung 840 PRO
|
Intel 730
|
AIO |
|
|
|
|
|
|
|
|
|
|
|
|
|
Total I/Os p/sec
|
7826.31 |
2425.72 |
5974.77 |
5450 |
2631.93 |
2934.20 |
MB/s
|
299.56
|
92.90
|
228.77 |
208.60 |
100.54 |
108.40 |
Average Response
|
0.1274 |
0.4118 |
0.1669 |
0.1831 |
0.3754 |
0.3324 |
Max Response
|
11.1732 |
12.619 |
7.1896 |
13.407 |
35.9 |
14.27 |
READ
|
|
|
|
|
|
|
Total I/Os p/sec |
39,561 |
35,838.86 |
33,273 |
26,705 |
28,647 |
33,414
|
MB/s
|
162.04 |
146.80 |
136.29 |
109.39 |
117.34 |
136.86 |
Average Response
|
0.025
|
0.0277
|
0.0298
|
0.0372
|
0.0347
|
0.0297
|
Max Response
|
1.5004
|
0.1722
|
1.3734
|
1.052
|
0.0972
|
2.7041
|
WRITE
|
|
|
|
|
|
|
Total I/Os p/sec
|
35,253 |
36,745 |
30,637 |
29,969 |
23,612 |
34,740 |
MB/s |
144.4 |
150.51 |
125.49 |
122.75 |
96.72
|
142.3 |
Average Response |
0.0281 |
0.0269 |
0.0324 |
0.0331 |
0.0421 |
0.0265 |
Max Response
|
15.37 |
49.1723 |
3.8156 |
1.1103 |
0.0548 |
15.308 |
This is an important benchmark that's designed to evaluate how drives can handle intensive workloads over longer periods of time – all of our benchmarks were run over periods of thirty minutes, rather than the near-instant tests we’ve used elsewhere.
The all-in-one test is designed to provide a general overview of SSD performance, and the Samsung's innovative memory modules helped it to a best-in-class result of 7,826UOPS at 299MB/s. The 850 Pro's average response time of 0.1274ms was the best here, too, and its maximum response result was the second-best on test.
The best maximum response in the all-in-one benchmark went to the 845DC Pro, which topped out at 7.1896ms. Samsung's write-heavy drive was the surprising runner-up in all of the all-in-one benchmarks, with a score of 5975 IOPS a few hundred points ahead of the 845DC Evo's 5,450 IOPS. Both of these Samsung drives also hit speeds of more than 200MB/s.
We can't be so positive about the SanDisk and Crucial drives. The MX100's overall score of 2,426 IOPS is the worst on test, and the Extreme Pro's 2,632 IOPS isn't much better.
In the 4K reading test the 850 Pro led the way, again, with an overall score of 39,561 IOPS and a 162MB/s speed. Surprisingly, the Crucial MX100 upped its game to come second with a score of 35,839 IOPS and a 147MB/s pace - and a max response time of 0.1722ms that's twice as fast as the Samsung drive.
The SanDisk climbed out of last place with an overall score of 28,647 IOPS, but it's still not impressive - far closer to the poor 26,705 IOPS of the 845DC Evo than the 850 Pro. The 845DC Evo's score is especially disappointing when its file-reading functionality is considered.
The Crucial MX100 didn't stop the shocks there. In the 4K random file benchmark its overall score of 36,745 IOPS snuck ahead of the 850 Pro's 35,253 IOPS to capture first place - and it was the fastest drive when it comes to MB/s speed and average response time, too.
In the random test, the 845DC Pro and Evo drives sat in mid-table, and the SanDisk's 23,612 IOPS result saw it adrift at the bottom of the five drives here, more than 6,000 IOPS behind the fourth-placed part.
Best SSD Group Test: Other Benchmarks and Features
The PCMark 7 storage benchmark simulates a host of real-world tasks that will be impacted by SSD performance, including importing pictures, editing video, playing music, booting applications, playing games and even basic Windows navigation.
It's no surprise that Samsung topped this particular table with a score of 5,602. That's a little better than its previous-generation drives, and it's a long way ahead of the SanDisk Extreme Pro, which scored 5,407 — only good enough for fourth place in this test. Intel’s drive returned a disappointing 5,367 points.
The Samsung 845DC Pro came second, with 5,546, and the 845DC Evo wasn't far behind with 5,435 points. The MX100 was the big disappointment, with a score of 5,270 being significantly slower than every rival.
PCMark 7
|
|---|
|
Crucial 256
|
845DC Pro 400
|
845DC EVO 480
|
SanDisk 480
|
Samsung 840 PRO
|
Intel 730
|
Secondary
Storage Test
|
5,602 |
5,270 |
5,546 |
5,435 |
5,407 |
5,367 |
The average temperature of the SSDs in this group has gone up since our last test, but we didn't have any concerns about the thermal performance of these drives: with temperatures that ranged from 33°C to 37°C, they're all cool.
SSDs used to be packaged with external caddies, screws and more extras, but that’s not the case these days – the declining price of drives leaves less room in the budget for helpful extras. In this group, only the SanDisk and Crucial drives come with anything in the box and, even then, they’re just bundled with adapters that can be used to fit their 7mm frames into spaces designed for older 9.5mm drives.
Some of this test’s drives make up for their lack of extras with generous warranties. The Samsung 850 Pro and SanDisk drives lead the way with ten-year deals – the first time we’ve seen such lengthy packages included with an SSD. Samsung’s other two SSDs include conventional five-year warranties, and the budget Crucial MX100 brings up the rear with three years of coverage.
Best SSD Group Test: Conclusion
The
Samsung 850 Pro is a perfect illustration of why it's important to control every aspect of a product, from research and development to manufacturing — and it's clear that it's the top dog when it comes to performance.
It topped the table in key tests across every bit of benchmarking software and, more often than not, it wasn’t far behind when it didn’t take the top spot. In our new IOmeter test it performed well, and it dominated in the Atto tests – a key indicator of good performance across the board.
The ten-year warranty is generous, too. If you’re searching for a high-end SSD, this is what you should be buying.
The SanDisk Extreme Pro has the same ten-year warranty and a near-identical cost-per-gigabyte figure, but its performance is too inconsistent – if you’re spending this much on an SSD, the Samsung is a better bet. That’s also true of the Intel 730, which didn’t impress in many of our benchmarks. If you’re looking for a budget drive then the Crucial MX100 is significantly cheaper, and if you’re after performance then the 256GB version of the 850 Pro is priced similarly to the £130, 54p-per-Gigabyte Intel.
Samsung’s two other drives are designed for reads and writes, and while both performed adequately in their respective tasks, their older hardware didn’t blow us away. They’re expensive, so they’re only worth considering if you need the reliability provided by their high endurance ratings.
The Crucial MX100 is an interesting case. It’s significantly slower than this test’s top drives in all but a handful of tests, but it’s also much cheaper – at £80 for 256GB and just 31p per gigabyte, it’s one of the best SSD deals we’ve seen.
It’s also a better bet than the older Crucial M550, which is still available. The M550’s £102 price is tempting, but its older technology is hampered in key areas – it’s able to keep up in sequential benchmarks, but in many small file tests it’s unable to match the speed of even the cheaper MX100 – and it’s even further behind some of the more expensive modern drives. It’s the same story with the Samsung 840 Evo – a once-great SSD that’s now suffering with poor small file speeds.
Bottom Line: If you want to get speeds that can outpace any hard disk without breaking the bank, the Crucial MX100 is a great budget option, but the Samsung 850 Pro remains our solid-state drive of choice.
Next, read our best Windows 8 laptops and tablet round-up
