Glo Networks Technical Blog (Glo Blog)

In a previous post we talked about the difference in disk read/write speed when enabling and disabling FileVault on a MacBook Pro fitted with an SSD. The software used to test was ‘Blackmagic Disk Speed Test’ which is available straight off the Mac App store.

Since that post there’s been an update for the software, and this update has brought something a bit fishy to our attention.

First let’s discuss what this update has changed. Directly from the product page on the App Store:

What’s New in Version 2.1

Some SSD’s use hidden compression when writing data to make their benchmarked speeds appear faster. Disk Speed Test will now measure the true speed of these SSD’s so you know if they are suitable for high quality uncompressed video capture.

The people that produce the software say the new update takes account for the ‘hidden compression’ used by SSD manufacturers, and measures the  ‘true speed’. So what difference does it actually make?  Here are some results we came up with:

Before Update	After Update

As you can see there’s a HUGE drop in the speeds the software reports! The SSD in question, a Corsair Force 3 240Gb SSD, is sold with the following specs listed:

Read Performance (max)             550 MB/s

Write Performance (max)            520 MB/s

The two logical conclusions that can come from this are:

SSD Manufacturers are artificially inflating the Read/Write speeds in order to put better looking specs on their SSDs

OR

The software, post update, is reporting things wrong or in an unorthodox manner.

There’s a few bells ringing here, this reminds us of the old hard drive capacity description discrepancy argument that went on for some time or possibly of the IPS broadband ‘up to’ speed claims issue.  Could we be seeing a similar overstatement from SSD manufacturers regards typical speeds?

Posted by James in Desktops and Laptops, General, Hardware, Software | No Comments »

So firstly what’s an SSD. In your computer you have a HD (hard disk drive) that is effectively some mini CDs spinning very quickly. These mini CDs store all your data and run your OS (Windows or OS X for the majority of us). They’ve been around for over 10 years and today you can pick up a 1Tb drive for under £60 delivered. Those spinning HDs run noisy, hot, slow and really don’t like to be bumped. SSDs however solve all those problems.

RAM in your computer runs a lot quicker than your HD and has a very different job. Over the last few years people have been in effect making HDs out of RAM. Think of HD technology as the steam age and SSDs are the oil age of cars.

We’ve recently put a 64Gb Corsair Extreme SSD in a PC and popped the OS on it (about £150 delivered). Loading programs and booting the OS are so much quicker. What caught us by surprise though was that when you load something you’re used to the whiring and clicking of the HD in the machine sitting next to you. This is completely done and actualy quite disconcerting to start with. We can see this obviously being of a huge benefit to laptop users and as such are keeping our eyes open for when the 300Gb SSDs are the right price.

Here are a few basic speed tests for storage in a PC -
1Tb Samsung 5400rpm HD
64Gb Corsair Extreme SSD
8Gb Sony USB Memory Stick
2 x 500Gb Samsung 7200rpm HD (RAID 0)
3 x 500Gb Samsung 7200rpm HD (RAID 5)

HDs will always have their place for mass storage but running your OS and programs on an SSD (or an array of SSDs) really does make a differnce. It’s as clear as walking 400 miles or flying 400 miles !

Posted by Chris in Desktop Hardware, Desktops and Laptops, Laptop Hardware | No Comments »