|Computer modding... with a soldering iron!
||[Monday 8th December 2014 at 7:11 pm]
|||||The Alchemist - Enigma [A Posteriori]||]|
I'm still waiting on some of the bits I ordered (one parcel appears to have disappeared between Overclockers despatching it and UPS receiving it - they're going to try again, hopefully with a more competent courier), but enough parts have arrived for me to start work on Nyx. So yesterday evening I stripped the system down with the aim of fitting a front panel memory card reader.
Now, the sensible way to fit it would be to plug it into a spare USB header on the motherboard. Except I don't (or rather, won't once the Overclockers order arrives) have any spare headers. The motherboard has three (each providing two ports) - two will be used by a front panel I/O module, and the third contains the built-in wifi daughterboard. Which in theory only needs one of the two USB ports, and has an unpopulated footprint for a header for the other port (it's even labelled). Can you see where this is going?
First task was to actually get the daughterboard out. It's screwed to the motherboard, but I found that if I removed all the PCI cards and slid the motherboard tray out a bit, then I could just fit a screwdriver in to undo the bracket. Motherboard trays are wonderfully useful bits of case design, especially as the alternative would be to completely remove the motherboard to get at the other screw on the back of it.
And yes, Nyx does have a lot of PCI and PCIe cards. Starting at the top above the blue 16x PCIe slot is a TP-Link TL-WDN3800 802.11n 300Mbps dual-band wifi card. Then there's an Adaptec SCSI card of all things for a Nikon Coolscan III film scanner. After that is an ancient ATi 3D Rage Pro PCI graphics card (yes, really - and if you look carefully, you'll spot a little SO-DIMM at the right with a whole 4MB of extra VRAM!) that I tried using as a temporary replacement for the 8800GT - unfortunately it's not even detected on this system. Finally at the bottom is a Hauppauge HVR-1100 DVB-T/PAL/FM TV/radio capture card (placed at the bottom to try to reduce EMI from the rest of the system). Though that's not quite as many cards as the predecessor Hector had (which at one point had every expansion slot filled, including the IDE slot).
And here's the wifi daughterboard. While there's a 6-pin header marked out, in reality only 4 pins are needed as the rightmost 2 are marked NC (not connected). That blob top middle is probably some sort of clear epoxy - yes, for some bizarre reason Asus have covered what's presumably a serial EEPROM (certainly it's the right size and pin count for one) in glue to stop anyone reading/writing it. Weird.
I dug the soldering iron out to discover that apparently soldering iron tips don't last long these days. This left me with either a massive chisel tip or a SMD pointed one, neither of which are quite right (I used the pointed one).
Ready for soldering with the pointed SMD tip. The placemat is there as I deemed it more expendable than the table :)
Eww, horrid lead-free solder. For non-electrical-engineers, the reason it's horrid is twofold: it melts at a significantly higher temperature (227°C rather than 188°C) than traditional 40/60 lead/tin solder, and it has a nasty habit of growing fine metal whiskers that cause short circuits. Thanks to EU RoHS directives though lead-free is all there is these days.
There's no action photos of me doing the soldering, as I don't have the fourth hand necessary to hold the camera (let alone the third hand to hold the PCB still while I've got the soldering iron in one hand and the solder in the other).
That's some of the worst soldering I've done in a long time. I blame the wrong choice of tip, the lead-free solder, and the fact that the tiny pads were next to an enormous ground plane (which here is a synonym for "heat sink"). Still, I have checked continuity and so it should all work. Time to reinstall it...
The photo is deceptive - in reality, the pins easily clear the heat pipe. Next is to fit the card reader, which goes in a 5.25" mounting bracket. For once I've got something that actually matches the colour of the case (black), albeit plastic rather than metal.
The bracket is also entirely plastic and came with self-tapping screws which are not the best choice... especially when the case is made of 2mm aluminium and the screws are rather short. Still, it's in and doesn't appear to be going anywhere.
Wired up! And yes, I did check before plugging it in which side of the plug went to the memory card reader and which went to the spare USB port (which won't be connected in my system - I really don't have enough USB headers to connect that up as well!). Time to power it all back up and see if it works...
As a side note, while rebuilding Nyx I accidentally swapped the graphics and SCSI cards round. On resuming Windows from hibernation (yes, I didn't even fully shut the PC down to work on it!) the SCSI card is now marked as missing a driver which is somewhat expected - the card isn't officially supported and so the driver needed some hackery to install. However there's now a new entry in Device Manager for the PCI graphics card. Oh, and the Firewire controller has been flagged up as failed.
Here was me thinking that Nyx would be less chaotic than Khaos was...