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Thursday, March 7, 2013

Netbook, Ultrabook, and Macbook Air Alternatives Continued

I've been looking further at some of the models mentioned in my previous post and it seems they are not without their idiosyncracies/foibles. The HP DM1 has a number of problems which may be potential deal breakers for those who are more technically inclined. These include:
- they use an Insyde BIOS which also uses a device whitelist which means that you may be limited with regards to hardware upgrades/swaps/replacements
- the wireless module on the system I examined was a Broadcom BCM4313 which may work under Linux but isn't the best solution out there. In fact, under Linux you may simply be better off using an USB based wireless module (use blacklist.conf/rfkill or even remove the wireless module to block/disable it). Swapping it out isn't an option though because of the whitelist issue! (more on this later) This is the error message if you're interested.
####Start Quote####
Wireless module not supported

The system has detected a Wireless module installed in the system is not supported. System halted. Please remove device and restart.

WLAN Module ID (702)

For more information visit: http://www.hp.com/go/techcenter/startup
####End Quote####
- we've mentioned the BIOS previously but I must mention it here again. Normally, there is an 'Advanced Mode' with many BIOS's or there are more options that are available in the open but I'm not sure what has happened  here. In the past, F12+A would allow you to access the 'Advanced Mode' but things have changed and you're left with an extremely stripped down version of what you would normally want (no options to turn on/off various capabilities (USB ports, wireless/BT, etc...), no choices with regards to SATA/ACHI mode, etc...)

Obvious ways around the BIOS/whitelist problem include:
- altering serials/ID's of devices, modifying the BIOS/whitelist, physically altering devices itself so that certain identifying information can't be gathered (create a secondary switch to make the device 'visible' again. If the machine doesn't support it obviously this could result in a smoky mess. You have been warned...) and so on but clearly these may impinge upon your warranty
- extracting BIOS/whitelist and finding compatible hardware so that you can work within whatever space is left
- creating an internally accessible (seen this mod with an Eee PC. Basically tap the internal USB bus, hook a hub to it, and plug a wireless card into that) USB wireless card. Some space in there but not much and there is already substandard thermal venting (the entire bottom side includes aluminium sheeting on the inside face, the frame uses some metal, and there are only two vents on the side. It should be noted that the machine can get extremely hot under maximum exertion) so not sure how it would go
- using a different/older BIOS. HP's utility doesn't seem to support downgrading though based on what I've seen. Hacks include using a different flashing utility or fiddling around with the extracted firmware/executables. Past experience with other manufacturers indicate that they often only make the most minor of efforts to obfuscate their work and reverse engineering may be realistic/possible
- modifying the BIOS itself, http://www.bios-mods.com/forum/archive/index.php?thread-4191.html

Having a locked down BIOS is understandable from a security, quality control, and other standpoints but this is seriously dumb for a device that is likely to be used in the consumer space. What's worse is that clearly not enough testing/research has been done with regards to providing a platform that will work across most operating systems...

For me these issues aren't really problematic. The real deal breaker here is the fact that the entire keyboard/moouse freezes from time to time. There have been numerous accounts of these problems and numerous supposed answers which include:
- build up of static
- faulty hardware
- incompatiblity with Linux (virtual machines are actually are realistic option on this particular machine but I often require raw access to the underlying hardware and I often use non-persistent/Live Operating Systems for testing)
- heat dissipation problems

Based on what I've seen it feels like there is a strong correlation with heat increases and keyboard/mouse freezes (everything else works except the keyboard/mouse. You can even plug in an external keyboard/mouse and everything works). I ran it with the following extra kernel boot parameter ("thermal.off=1") which offloads thermal management from the OS to the BIOS and it seemed to work. Then, I ran a simulation by running multiple instances of dd running pseudo random number generation and outputting them to stdout.
dd if=/dev/urandom of=/dev/stdout
This allowed me to increase system temperature without requiring significant user interaction. Thereafter, it was a case of watching whether or not the system would keel over. One night of testing and I thought that I had may have overcome the problem but after doing some intense network based wireless transfers it seemed clear that I had not. Moreover, attempting to cool it via air-conditioning seemed to have no effect. If I had more time this would be a non-issue since I could work away at the problem until it's fixed but the fact of the matter is I'm busy at the moment....

Still, I honestly believe the DM1 is a strong offering (screen, keyboard, battery life, and so on) in spite of these problems. If HP are willing to make the necessary modifications (and offer better/stronger support for their product) they clearly would have one of the strongest options in this particular market sector/price point.


A utility to allow for more better temperature control/battery life on your laptop


Work with enough audio equipment and you'll eventually get crackling at some point. Often you think it's the speakers or the cable themselves but they're often the connections. Replacement parts are available from local electronic stores.

- as usual thanks to all of the individuals and groups who purchase and use my goods and services

Quick Beef Stew Recipe, Random Stuff, and More

This is the latest in my series on quick, easy, and tasty meals:   http://dtbnguyen.blogspot.com/2017/11/chinese-style-congee-jook-recipe...