Magitech.ca written by Wyatt Zacharias

m.2 PCIe SSD Failure Symptoms

I ran accross an interesting hardward failure the other day in a fairly new HP Elitebook, however, initially I didn’t even realize a hardware failure was the cause of the issues encountered. When booting the laptop it would sit on the “HP Sure Start” screen indefinitely, without even reaching the bios. My first thought was that something was buggered with the TPM module (which is responsible for the HP Sure Start screen ahead of the bios), but with no error message from the TPM and being unable to reach the bios, I started trying to hard reset things as best I could. After removing about 20 tiny screws from the back cover and prying it off I was able to reach the laptop’s main battery, as well as the cmos battery. After leaving the laptop completly unpowered for several minutes I tried booting again, but still hit the same dead end as before. At this point the only option left was to remove every module possible, including the system RAM, and see if I can even get some angry beeps from the bios about missing hardward. Success! With no RAM and no HDD the bios will at least beep at me that something is wrong. Now working backwards, I started with just the system RAM but no HDD, and voila, I get a bios complaining about no bootable disks, and the option to enter setup. Now even up to this point I still wasn’t convinced that the SSD was actually the problem, since the laptop was only a couple months old at this point. However, even after defaulting and resetting the bios and TPM several times, I still could not get past the HP Sure Start screen with the SSD in the laptop. After sending the machine to the HP repair depot my diagnosis was confirmed when they returned the machine with a new SSD replacement.

An interesting complication of these new PCIe based hard drives, if the controller on the drive fails you end up with a dead PCIe device, which the bios will hang on trying to initialise. This could make data recovery off these drives much more complicated since there’s no way to even attempt to read data off the drive if your bios can’t initialise the PCIe device, even if you have another drive to boot off of.

Windows Re-Sorting Directory Every Time

Something that’s been annoying me ever since I started using a new Windows 10 desktop is that every time I would open my Downloads folder, which usually contains several hundred random items inside, Windows would take upwards of 5 seconds each time to sort the directory by date. This was the first time I had ever seen behaviour like this, and although my first instinct was to think the number of files in the folder was slowing it down, a couple hundred files is virtually nothing. After flipping through several windows forum posts where “expert contributors” were suggesting everything from virus scans to full re-installs I came across one single post that had the killer detail I was looking for. That detail was make sure the column you are sorting is “Date Modified” and not just “Date”. If one was not looking closely it’s easy to see how this could be missed, and if you don’t have both the “Date” and “Date Modified” columns set to be visible, you could just assume that the “Date” column was the Windows default, and the right choice. The explanation given in the forum post is that “Date Modified” is a file attribute attached to the file, while “Date” is not, and thus has to be calculated by Windows every time the directory is opened.

Wireless Theory and Regulations in Canada

A couple months ago at Muug I did a presentation on the basics of wireless theory and the Canadian regulations regarding unlicensed wireless usage. The first three quaters or so of the presentation covers the wireless theory, including things like decibels, radiation patterns, coaxial cable, fresnel zones, and more. In contrast to most other information sources, the regulations I cover in the last quater of the presentation are those created and enforced by Industry Canada who is responsible for wireless regulation in Canada. If you’d like to have a look at the slides from the presentation, they are availble in pptx and pdf format at the links below. If you’d like to see more topics on radio go checkout my ham radio focused blog at VE4WDZ.ca

WirelessTheoryAndRegulations.pptx
WirelessTheoryAndRegulations.pdf