How to test your SD Card Speeds & more followup to my ongoing issues

Hello Readers!

Following up to my previous Article, I continue the saga as well as tell you about a free piece of software I found that allows you to properly speed test your Sd cards!

The Software is called AJA System Test and is free to download from:

I’ll get to that software in a minute but first an update to my current SD Card story….

Lexar Update (as of October 29th, 2018)

I still have no cards from Lexar…

That’s the first part of the bad news. The good news is that Lexar gave a rather tentative timetable by the end of the month as to when they will have newly labeled products and can ship out cards to its warranty claims at the earliest.

However, The second bad news is that I keep checking in with them and their support agents are now continuing to delay my requests and are now trying to pay me off with less than the value of the cards that I paid for…

6 weeks in folks… still no cards or valid amount of money as compensation.

Which means that if i were to accept payment from them.. I would no longer be able to afford the correct cards for my camera due to the increases.

These are what I call.. Bad Warranty and customer service (and even criminal to a certain extent) policies.

A warranty program that refuses to or simply can’t supply the needs of their customers and also lie about specs (such as the UHS-II Write non-capable issue or listing higher performance than is true).. it’s not only dishonest, its consumer fraud.

In response, I’ve now asked to speak to a senior financial executive who has any kind of authority to remedy this situation.

Folks.. This is a clear case of bad warranty service for professional products.

Other memory card makers should take notice. Make good products and support them well. Yes its expensive to do so but you just need to give the customer what they want!

Because memory cards and performance and speed are so closely linked to being productive on the customer side.. Professionals simply can’t afford this nonsense and in the long run, it will end up costing companies who do these ridiculous customer services practices and harm to their own bottom lines later on.

I understand that companies will struggle with supply & demand issues during memory card pricing or production issues or that natural disasters and political trade issues can play a part but companies had better pay up and have those funds ready to support customers needs and be ready to be more flexible for demands if they want to continue to be in business. That’s just a fact of doing business.

You could argue the same for me. That i have to be more flexible… the answer is you are correct!  That’s exactly what I had to do here because I can’t run a business or my life on the timetable of one external mismanaged company..

Further info on this label delay news:

Now the reasons behind this delay were clearly stated to me. In order for Lexar to comply with U.S. law requiring them to properly display data on their cards they have to relabel before shipping out products which don’t fit that description. This tells me two things.. One.. The company has done something wrong and is desperately trying to fix their legal mistake (which was stated to me in the email) and most likely there are other external factors at work such as limited supply and the company can’t fulfill its warranty promises. Quality control may also be another issue at hand.

Clearly something has to be done to address the issues, there is at least some progress in my communication on Lexar’s part (except for the set back today)  however for me, I am still without cards (now going on Week 6 at the time of this article). It is still uncertain as to when or if I will receive my replacement 128Gb 1000x 150 MBps replacement cards (2) any time soon and whether they will in fact perform to my expectations that i need for my GH5?

I can’t in good conscience recommend any company that doesn’t offer to assist its customers and would rather put them over a barrel to protect minor profit margin for short-term gains than sacrifice long-term customer loyalty especially for a professional branded product.

I’d love to hear from everyone on their experiences with warranty replacement issues with Lexar and other companies and whether or not you got results!

This story as of last week, was forwarded on to CBC’s Marketplace in hopes that some more investigation can be taken to shed some light on the memory card industry from a consumers point of view. Consumers deserve better and more concise information in order to make informed decisions about the products they are buying. When manufacturers mislead or misrepresent factual information it leads to mistrust and ultimately hurts the industry as a whole. As the new technologies and standards come out for video products manufacturers have to keep the customer at the center of their business focus from sale to warranty service. For professionals, trusting your gear is essential.

As for my situation with Lexar.. I am hopeful they will in fact ship me the product i am owed so i can now move on to actually doing what i need to do.. create..


Is it coincidental then that the word Angel is in the name of the next memory card manufacturer?

In my case, even though i am not religious.. the name fits. This really was saving my bacon and a relief to find a manufacturer that stands by its performance specs..

With Fears of buying even more problems due to the high price and uncertainty of buying memory cards.. I initially was skeptical but then I found AngelBird Technologies.

Their website and specs were upfront..

Even though my wallet was empty, I thought that I had to somehow carry on. After all, Youtube and much of the content I like to produce now is shot on the GH5 and not my older camera, I Decided to bite the bullet and take a chance on this company.

This company specializes in Audio Visual Equipment and has its own Brand of SD Cards made for media professionals. Their cards are manufactured in Taiwan but the company is an Austrian company. The other exciting news is that they have V60 labeled cards! V60 cards as you all know have been most difficult to find on the market at decent prices. Not as fast as V90 cards they are totally suitable for the GH5 at quoted speeds.. and their cheaper than buying V90 cards at the moment (saving almost double the cost).

Angelbird also has V90 cards (but are currently expensive) and they also have the option of shipping in pairs. For GH5 users they also have a specific SKU for purchasing. they make sure to have tested matched pairs of SD cards which is a necessity for Dual Backup operation on the GH5. they also come with a 3-year fulltime warranty from Angelbird.

One thing I noticed in the spec sheets was that these cards have ECC (Error Correction and Control) logic to reduce errors. ECC memory has always been more expensive but more reliable in terms of bit corruption. To any techies out there, you will appreciate this! They are also SD Card Bus Specification version 5.0 (more on this later)

Initial testing on these cards so far has been great and the card lives up to its minimum standard of V60 (Minimum sustained of 60 MBps). More than enough data rate for the GH5’s much-needed 50 MBps (400 Mbps). more on this in a minute.. (See Actual testing rates later on in the article)

The only drawback is currently that Angelbird is in Austria which means shipping via UPS to Canada (where I am) can be expensive and not straight forward at times. Sure enough i did have troubles with UPS over being miscategorized and initial quotes were very high for clearance charges. In the end after several days of trying to get quotes and more manageable business rate for the charges, the package finally arrived.

Angelbird itself is working on this and I provided them some feedback in this regard. Finding a good trustworthy manufacturer that is upfront about its specs and labels and supports its customers is key to providing a partnership that Video professionals can work with. So far Angelbird seems to be a winner here.

You can order directly off their website here (I get no commission from the sales):

My Testing Process Flaws & Correction

In my previous tests on the Lexar cards I was using a program that was not built for the various SD card memory and clock modes that the testing didn’t take into account. The program only was for general USB/flash throughput testing. Clearly the Lexar cards were skipping frames, corrupting video files etc regardless however the speed tests I performed were inaccurate as a proper measurement. The Testing although not proper standards did show inconsistencies between those two cards which was at best a good indication that both cards had issues. Further reserach led to concluding through external testing websites that in fact those cards I had did not allow UHS-II writes speeds anyways! This was a big shock to me at the time. Therefore for the GH5 they were supposed to work in did not perform properly. The cards were also not V60 labled and rated but had WRITE speeds quoted 80 MBps or above and tests showed at least 75 MBps on other testing websites which at the time seemed logical for the GH5. confirmed them as “not Writing at UHS-II speeds” even though it had UHS-II on the label!

Since the GH5 and other cameras don’t write well at slower UHS-I speeds (again something new i learned during all of this) due to their controllers, This becomes a problem for all GH5 users.
This very misleading marketing practice to the purchasers of these cards thinking they are getting one thing and not getting what they paid for is to say the least very unfortunate.

Going forward I will be using AJA System Test for all cards as it’s clearly a more robust and standardized testing tool that can read at least SD card standard 5.0 and I’ve had great results so far with it.

I would argue that Standardized testing needs to be implemented for this industry so that customers can verify what it is they are purchasing and whether they are getting what they paid for.

AJA System Test

The Software allows users to essentially configure their testing parameters to what type of footage and the size of their footage and then the test writes that file to the card all while collecting data during the write. the interface is simple and shows effectively the transfer rate of the sd cards you are writing to. Files can be Simple 720 MP4 files to GH5 10-bit YUV 4K files or even Red RAW footage and it will show you how the card would handle it.


For this test I used the only other Lexar SD card I had which is a 64 GB 1000x 150 MBps Professional card.. Its got a Gold label and clearly states UHS-II speeds as well. This card however has worked flawlessly however I primarily use this card on my Canon T6S which doesn’t have 4K and the bitrates are a lot less.

Testing this card we see that the Write Speeds are in fact a decent 75 MBps. This card


** Note: One thing to consider here is how good of a SD Card reader you are using if you run the tests external tot he camera. Also, In camera SD card performance to a PC typically is less on the GH5 in my experience. Having a good SD card reader at version 4.0 or 5.0 SD card standard is essential for testing otherwise the card reader will not know how to communicate properly with your card and may give incorrect values. Also having all of your Motherboard Chipset and USB 3.0 or 3.1 drivers (Windows) up to date if you are using a USB card reader (USB 2 port is not recommended for this test). I also recommend Windows 10 for this test as previous OS’s may not fully support the speeds.

The application even allows customizing the settings.

Note: that when I tried setting the Disk cache to enable, I got worse results. This could indicate the the native transfer modes of the card and cache on-board the card itself may play a role in its performance. Also considering most Video files write sequentially there wouldn’t be anything to cache.

The setting shown are pretty much the defaults when it comes to testing performance so i recommend you leave them alone.



The next important section is the System report. This can show you the graph of the writes and read tests and also show you the minimum and maximum speeds that the test encountered. this is extremely useful to see where these cards are at in terms of performance. Note: that I un-check the generate .nfo file as that is more for technical support to read further details about the system the test was run on more than the results of the test itself.

Angelbird Card Initial Testing

For my initial tests.. Angelbird cards look good albeit not exactly as they claim but they are more in the ballpark than Lexar!

Here are the two speed tests (after several different writes using various video test files).

128 GB V60 – Card 1

128 GB V60 – Card 2

I also managed to record a couple of minutes at 4K 60 as well as 4K 24 @ 10-bit 4:2:2 and the cards seem to handle things okay. They also were able to write to both card slots simultaneously which means I am now able to shoot with a backup file in case something happens to one of the cards. Very important for certain shots or work.

Although they quote 105 MB/sec sustained on their website, I am chalking up the slower speed here to windows and my older systems USB 3.0 driver performance.

For those wanting to know what USB card reader i’m using.. you can purchase it here:

Another Thing to consider when buying SD Cards – Part 2

Another Specification when buying SD cards which was not obvious is the age of the card when it was manufactured. This will tell you aproximately to which standard the card was made. You can tell what type of card it was either an SD, SDHC, SDHC with UHS-I, SDHC with UHS-II

The Bus speed of a Card is determined by the SD card Specification Standards. The SD Card Standards website describes each version of the specification in more detail.
check out for more details.

Here is a list of the Various SD Card Standards and the information and insight I’ve gained:

Standard Version (Year) Maximum bus speed write possible Minimum Sustained write speeds Card type version introduced
Default Bus Speed (SD) Ver 1.01 (First cards) (around 2000) Up to 12.5 MB/sec Sequential Write speed unknown SD
High Speed Bus (SDHC) Ver 1.10 to ver 2.0 (2006) Up to 25 MB/sec Sequential Write speed 2 MB/sec, 6 MB/ sec SD and SDHC (would include Class 2, 6 devices initially)
UHS-I (Ultra High Speed Bus) ver 3.0 (2009) Up to 50MB/sec (SDR50, DDR50 2- lane memory clock mode)
Up to 104 MB/sec (SDR104 – 4 lane memory clock mode)
10 MB/sec, 30 MB/sec SDHC, SDXC (would includes Class 10, U1, U3 devices)
UHS-II (*two rows of pins on back) ver 4.0 (2011) Up to 156 MB/sec (half duplex)
Up to 312 MB/ sec (full duplex)
same as above but varies from manufacturer to manufacturer. SDHC, SDXC
UHS-II (improved classes) ver 5.0 (2016) same as above.. improved sequential writes 30 MB/sec, 60 MB sec and 90 MB/sec SDHC, SDXC (V30, V60, V90)
UHS-III ver 6.0 (Feb 2017) Up to 312 MB/sec (FD312)
Up to 624 MB/sec (FD624)
same as above or higher SDHC, SDXC (V30, V60, V90)
(with more standards expected as higher card speeds are produced for video and high bitrate codecs)
SD Express (SDUC) ver 7.0 (June 2018) 985 MB/s (FD985) same as above or higher SDUC

I hope this information has been useful to some of you.

Please share your experiences!

Now… Back to creating!


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