Intel 520 Series 240GB full review

As well as its main line in PC processors, Intel now offers an expanding selection of solid-state drives (SSDs). The Intel 520 Series sits near the top of the company’s range, promising sequential read/write performance of 550 and 520MBps, and up to 80k write IOPS. 

This is a latest-generation SATA 6Gbps drive for the enthusiast and power user.

Perhaps surprisingly for the silicon-tech giant, Intel does not always develop its own controllers. Here for the 520 Series, it is licensing controller technology from SandForce, one of the leaders in this key component of every SSD.

However, the firmware loaded on the SandForce SF-2281 controller chip features Intel’s own customisations, codenamed Cherryville. 

Given Intel’s reputation for exhaustive testing, this is likely to result in an SSD with better reliability than we’ve heard can be found on some SandForce-powered drives. 

Alongside that SandForce front-end, potentially unlocking the fastest reading performances, Intel is also using the latest NAND flash storage. Here we find 25nm MLC, developed in conjunction with Micron.

The Intel 520 Series SSD is available in a choice of capacities: 60, 120, 180, 240 and 480GB. We tested the 240GB model.

Rather than the usual 9.5mm-high form factor, the Intel 520 Series is available in 7mm height – lending itself to installation in modern ultraportable notebooks that require the thinnest physical storage. 

Our sample had a removable plastic spacer to bring it up to 9.5mm height, although with no replacement short screws provided in the box, you’ll have trouble reassembling the drive without the spacer.

The SSD chassis is made from thin pressed aluminium, not as luxurious as many premium solid-state drives, but making for a very lightweight SSD at just 84g.

Intel 520 Series 240GB: Performance

Using the straightforward and always-flattering Atto benchmark test, the Intel 520 Series 240GB could reach 525 MBps for sequential writes and 558 MBps for reads. 

In fact, these results are identical to another SandForce SF-2281-wielding SSD we tested recently, the Kingston HyperX 240GB. 

And very similar results were spotted in the CrystalDiskMark 3.0 test too. Here the Intel 520 Series 240GB measured 475 for reads and 305 MBps for writes, against the Kingston’s 492 and 308 MBps respectively.

Both these drives’ subdued write performances are well below advertised figure of over 500 MBps, but this is simply because the SandForce controller inside only achieves its blazing write speeds with a limited file type – namely compressible data. 

Sadly, the real-world large files that are most in need of Intel’s headline 520 MBps write speed are more likely to be media files (MPEG, JPEG etc) or large .iso files. These files typically cannot be further compressed losslessly, so data will be written at the much lower speed of around 300 MBps. 

In this increasingly security-conscious world, whole drive encryption is becoming more popular. An encrypted drive effectively holds randomised data, which also cannot be losslessly compressed by any useful degree.

Note, however, that while 300 MBps is relatively slow in solid-state terms, it’s still around twice the speed of the fastest hard disks. 

Turning to another contemporary SSD by way of comparison, the Corsair Performance Pro 256GB, we measured CDM read/writes at a more consistent 452/406 MBps, regardless of data type.

At the small file level, the Intel 520 Series showed 4kB read/writes at 36/99 MBps. When increasing the queue depth to 32, this increased to 229/265 MBps.

Turning to the AS SSD benchmark, we measured read IOPS up to 62k and write IOPS to 59k. This is close to the results from the Kingston, which instead favoured writes over reads, here measuring 53k read IOPS and 60k write IOPS.

These are all excellent figures, if short of the fastest SATA 6Gbps SSD we’ve seen, the Corsair Performance Pro, which achieved consistent 69k and 62k IOPS, reads and writes respectively. 

(The Samsung 830 Series 256GB was capable of even higher read IOPS, measured at 74k, at the expense of write IOPS, which fell to just 24k.)

The Intel 520 Series had an overall nominal score of 798 points in AS SSD, against 871 for the Corsair and 760 points for the Kingston. 


Intel 520 Series 240GB: Specs

  • 240GB SSD
  • SATA 6Gbps
  • 2.5in form factor
  • available in 60GB, 120GB, 180GB and 240GB capacities
  • SandForce SF-2281 controller
  • 25nm MLC NAND flash
  • < 1 sector/10 16 bits UBER
  • 1.2 million hours MTBF
  • 100 x 70 x 7mm
  • 84g
  • 5-year warranty