Switched On Tech Design

Author: sotech

  • ZFS on Ubuntu error: Failed to load ZFS module stack

     

    If you see the above error in a fresh installation of ZFS on Ubuntu one cause may be that the package build-essentials wasn’t installed prior to installing the ubuntu-zfs package; run:

     

    sudo apt-get purge ubuntu-zfs

     

    then check for the remaining packages with the following:

     

    dpkg –list | grep zfs

     

    …and apt-get purge any remaining relevant ZFS packages.

     

    Then:

     

    sudo apt-get install build-essential

     

    …then install ubuntu-zfs as you did originally:

     

    sudo apt-get install ubuntu-zfs

     

    This time it should take properly. This isn’t the only cause of that error but on a fresh install with a new OS it’s one possibility.

  • Testing new power supply: Corsair VS450

    We got a new unit in-house that we’re trialling – the new Corsair VS450 entry-level PSU.

     

    Featuring 450W of output, a single 12V rail, two PCI-E connectors and a 3-year warranty it provides an interesting option for builds with a single midrange graphics card. We’ll post back if we find anything interesting in our tests – in the meantime, here’s a couple more pics of the unit:

     





     

  • Right-angled SATA cables

     

    Having trouble with routing SATA cables in a tight space? Don’t forget that you can get SATA cables with connectors at a variety of angles, including 90 degrees to the side:

     

     

    This can make routing cables quite a bit easier – sometimes allowing you to avoid pressing the cable in at an odd angle or putting pressure on the connector (which can break your $100+ drive rather than your $5 cable). The other end can be straight or 90 degrees – straight is usually the most handy for the motherboard end:

     

     

    They’re around the same price as a regular straight-ended SATA cable – only a few dollars each, which is well worth the investment if it means avoiding putting strain on your drives or potentially damaging the cable through awkward routing.

     

     

    Hope that helps someone who didn’t know they existed!

  • ESXi: Accessing datastores via web browser

     

    This is one that a lot of people don’t seem to be aware of – did you know you could access your ESXi server’s datastores via a browser? It’s a convenient way of grabbing copies of ISOs or patches stored on your server for burning or use elsewhere. It’s set up automatically with ESXi – simply enter in the IP address of your local ESXi server and you should see a page akin to the following:

     

    Click on the link on the right-hand side to view the datastores and you will be prompted for a login:

     

    Enter your login – usually the root login you created when you installed ESXi. From there you should be taken to a page where you can see a listing of all of your available datastores:

     

    From there you can browse the contents of the datastores and download files as you please! It can also be handy as a quick way of viewing log files.

  • Ubuntu: Clear terminal screen

     

    Sometimes you may wish to clear the terminal window, whether it be to hide what you’ve just done, clear some irrelevant/distracting output or any other reason. The best command to do this is simple:

     

    reset

     

    This completely clears the output shown in your terminal window but doesn’t log you out. If you want to keep your output in the buffer (i.e. so you can scroll back up to it) but still clear the terminal you can see you can use the following key combination:

     

    ctrl+L

     

    This pushes the output up above your prompt and puts the prompt at the top of your window.

     

     

  • Network Troubleshooting: Wireless N connecting at 54Mb/s

     

    This one came up today with a customer who was extending her Wireless N home wifi network with a wireless access point. The access point was reporting a Wireless N connection at a speed of 54Mb/s rather than 150 or 300Mb/s, and transfer speeds for anything connected to the access point were only 2-3MB/s (not unusual for 54Mb/s). The problem in this case ended up being that the access point was set to TKIP encryption rather than AES – using either WEP or WPA-TKIP may drop speeds back to Wireless G speed, which is 54Mb/s max.

     

    Switching the encryption to AES put speeds back to what they should be. This won’t always be the solution but it’s worth checking if you’re seeing that issue.

  • Intel i5-3470 vs i5-3570

     

     

    The above two CPUs are often shortlisted for entry/midrange gaming builds that aren’t overclocked; so how do they compare?

     

    Both are quad-core CPUs without hyperthreading, so they offer 4 cores and 4 threads. The i5-3470 is clocked at 3.2GHz while the i5-3570 is 200MHz faster at 3.4GHz, and both CPUs feature Intel’s Turbo Boost v.2.0, reaching peak speeds of 3.6 and 3.8GHz respectively. This equates to ~6-7% performance difference if you’re running both CPUs at max. Both feature Intel’s HD2500 graphics – according to Intel’s ARK the i5-3570’s graphics are clocked fractionally faster – 1.15GHz as opposed to 1.10GHz, which is a negligible difference.

     

    The i5-3570 is about 10% more expensive than the i5-3470 – 10% more cost for 6-7% more CPU performance isn’t bad, though you can’t really go too far wrong either way – if you’re $20 off a better graphics card you’re probably better off going that way and getting the i5-3470, whereas if you could do with a touch more CPU grunt it’s likely worth your $20 to grab the i5-3570.

  • Intel SSD 330 benchmarks coming soon…

     

    We finally got around to starting our benchmarks for Intel’s 330 SSD – will post them once we’ve tested it across another system to get some averages. Check back soon!

     

  • Palit GTX 650 Ti – A visual overview and mini review

     

    One of the best gaming cards for those on a budget at the moment is the GTX 650Ti, and one of the most cost-effective models is the Palit version. Clocked at 928MHz with a memory clock of 2700MHz, it supports up to 2560×1600 resolution (or 2048×1536 over VGA).

     


    As you can see it’s a reasonably short video card, with the PCB measuring just under 17cm long. It has a maximum of 100W power draw, and thus only requires a single 6-pin PCI-E power connector which is positioned at the end of the card:

     

     

    There is adequate room over the clasp to remove the cable without too much fiddling.

     

     

    The card is a 2-slot design and has VGA, DVI and mini-HDMI outputs.

     

     

    Here we can see that the fan shroud does not extend very far past the PCB, and that the cooling fan exhausts the hot air back inside the case. Given that the card shouldn’t produce a great deal of heat this may not require additional cooling if your airflow is already reasonable, though it is something to keep in mind.

     

     

    Nothing remarkable at the top of the card – there’s enough space for some air to escape after passing over the hot components and little else.

     

     

    The fan is a 13-blade design and is reasonably quiet in day to day use – not surprising given that the card isn’t producing a great deal of heat.

     

     

    The plastic shroud next to the fan is stylized somewhat – enough to make it look interesting without going over the top. There’s some faint patterning along the length of the card:

     

     

    For around $150 the card represents a cost-effective way of getting much better graphics performance than the integrated CPU graphics of either AMD or Intel. Also worth noting is the card’s 2-year warranty. The new architecture from Nvidia is more power efficient than the previous which means that the card not only uses less power but produces less heat, which means less effort to keep it cool and lower noise levels as a result. Overall, Nvidia seem to have a winner on their hands here and I wouldn’t be surprised to see this or another 650 Ti variant making it’s way into a fair few of our budget gaming builds.

     

     

  • Asus Pike 2008 SAS card

     

    We have finally got one of these cards in-house for testing;

     

    We’re particularly interested in how it compares to cards like the M1015 in IT mode as an inexpensive way of adding 8 SAS/SATA ports to a storage server. Expect a post soon reporting on what we find!

    You can buy the Asus PIKE 2008 card from Amazon.com: