Tuesday, 29 July 2008

Crazy from the Heat...

Computers don't like heat. Apparently. Years ago, I was putting together a system for my brother based on one of the old AMD Athlon CPUs.  Built it, tested it, installed Windows, everything running beautifully. Fire it up an hour or two before he arrives to pick it up... it bluescreens and won't boot. Open up the case, check everything's seated properly... you know the drill. It's all fine, of course. Three hours later, I still can't work out what's wrong. Every component is fine. Every diagnostic passes. The disks are fine. The memory is fine. Eventually, and completely by chance, I actually move the case off the desk onto the floor whilst it's running... and it crashes. Turns out the heatsink clamp was ever-so-slightly bent out of shape. Unlike the LGA775 heatsinks of today with their wonderfully-engineered motherboard mountings, the old Athlon heatsinks just clipped onto the plastic CPU socket, and what was happening was that when the box - a generic mini-tower case - was up on the desk, on its side, running tests and diagnostics, everything was fine. When I put it back together and flipped it the right way up - i.e. standing vertically - the weight of the heatsink combined with the bent clip was just enough to pull the heatsink out of contact with the CPU, which would then shoot up to 96°C and crash spectacularly. A new heatsink clip and some arctic silver and it worked perfectly.

Anyway. Moral of the story is, in my experience, PCs go funny in the summer. Whether it's the heat or just plain coincidence I don't know, but they do. And when they do, the first thing to check - always - is the memory. Get the Ultimate Boot CD, load up MemTest86, and let it run overnight. (If anything's wrong, it generally shows up in about two minutes... but if it'll run overnight without any problems, your RAM is almost certainly OK.)

Faulty memory creates the most bewildering array of crashes, faults, errors and bluescreens I have ever seen. Having inadvertently run a system with a stick of bad RAM for a couple of weeks, I would at various points have sworn it was the RAID controller, the hard drive, the video card, Windows, the printer driver - in fact, pretty much every component of the system seemed to have caused it to crash at one point or another. I'd ignored the possibility of the memory, because the system in question isn't that old and it was tested when I put it together... I was wrong, and just running Memtest86 in the first place would have saved literally hours of troubleshooting and head-scratching.

Gadgets and Gizmos Time...

We're on a green drive. London is having a full-fledged heatwave, the temperature is regularly hitting 30°, and sitting in a room surrounded by electrical equipment that basically sits there spitting out heat all day suddenly doesn't seem like such a good idea. When you realise that all that heat is basically wasted electricity - that I'm paying for, and then trying desperately to push out of my windows to cool the room down - a little geek spring-cleaning suddenly seems like a pretty good idea.

Belkin N1 Vision First off, last month I replaced the motley collection of switches, DSL routers and wireless access points - along with their accompanying individual power supplies - with a Belkin N1 Vision. This truly wonderful gizmo combines a DSL router, four Gigabit wired ethernet ports and draft 802.11n, in a really innovative package. The LCD readout on the front is frankly genius. Download monitor; wi-fi status readout; desk clock, DSL speed meter - it's intuitive, versatile and just very, very cool. And it works. I don't have to keep unplugging it to get wi-fi working again, like I did with the old one. The DSL automatically comes back on when power is restored (a major gripe I had with my old Speedtouch router). I love it. My computers love it. Maria's iPhone really loves it. And it's fast enough to watch movies over wi-fi from pretty much anywhere in the house.

wdfMyBook_World_2NThe really neat part, though, is a Western Digital My Book World Edition II. It's basically two cheap SATA hard drives in a box, with a fan and a low-powered CPU running a cut-down version of Linux, and some dreadful but completely optional Mionet software. You might remember these as the subject of some truly awful press coverage last year. The truth is, the supplied (but optional) MioNet software won't share certain file types with anonymous users over a public-facing connection. The press picked this up as "network hard drive won't share files" - which is almost total bollocks - and ran with it.

But I digress. Despite the apparently slow network interface, it works - easy to set up, easy to get files onto it, easy to get them off again. The fun really starts, though, when you work out how to get console access to the onboard Linux OS. (Neat tip - once you've got SSH access, it's much quicker to transfer big files - music, video, etc. - by copying them onto an external USB drive, plugging it into the back of the MyBook, SSHing into the console and copying it onto the internal HD using Linux 'cp' command, than to copy them over the network.) With a couple of evening's tinkering and copius assistance from the wiki at mybookworld.wikidot.com, it's now acting as an iTunes media server (via MediaTomb) and print server. The kind of stuff I used to leave a "proper" PC running 24/7 to do. The print server, in particular, is very neat - any computer in the house, including wireless, printing to a completely normal USB Canon Pixma iP5300, and it's even smart enough to work with the printer's power-save features... send a print job, printer wakes up, prints it, and goes back to sleep with nary so much as a standby light.

Basically, the "infrastructure" - file server, wi-fi, DSL, printing support - that all the other computers rely on is now running on two small appliances and a printer that only switches itself on when it's needed. I'm going to get one of those electricity meter things to get some hard stats on how much power this lot actually draws, but in the meantime it's definitely cooler and quieter than a full-blown server and pile of networking gear - and I figure that has to be good for the electricity bill and the planet. Not to mention how much fun it is doing things that aren't supposed to be possible in the first place.