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[tickmike]

For some weeks now I have been having the internet dropping out and it's been getting worse 

The Netgear DG834GT (with the DG team firmware) was mounted on top of my network switch which is on the top of my hardware firewall (Smoothwall on an old PentIII computer) they all are in the bottom of our meter cupboard and has been like that for about a year with no problems .
It does not get hot in there !.
I have been changing the settings, checking the logs etc, etc for a few weeks and after it dropping the connection some 30+ times today I went to put my old 'Speedtouch' router back and nearly burnt my fingers  The router was very hot (so was the network switch)
So the first thing I tried was to just hang the router in mid air and it started to cool down and NO More Drop Outs 
Doing a internet search I found some details about what other people had done
eg, http://www.hack247.co.uk/netgear-dg834gt-cooling-mod/
So what I'm going to do is to fit a heatsink and fan (off an old CPU) like the bottom photo on that webpage.
I will report back .

[sevenlayermuddle]

I've had one of my DG834GTs fail, and also a Netgear gigabit router in identical packaging.

In each case, the failure was electrolytic caps.  My current DG834GT  is already on borrowed time as its caps have also started to bulge. 

The lifetime of these caps  is dictated by a well-understood chemical process that is directly impacted by temperature, so cooler running may indeed  help.  So might better component quality.

But if you want to extend the life of these routers and switches, and you are willing to wield a soldering iron, then IMHO you'd be better off just junking the cheap caps that factory  fit, and replacing with decent high temperature rating Panasonics  (or whatever).   That is probably less bother than modding the cooling arrangements, yet still achieve the goal of longer life.

[tickmike]

I already have them marked up for changing as two are bulging now, I have 4 of these routers off 'Freecycle' and one is still new and still in it's box. 

[neilius]

A bit off topic but I was round my parent's house yesterday and I started to smell burning in the living room. A moment later there was a loud bang that came from the area his TV was sited. The TV (an ld Panasonic CRT) wasn't on at the time either, nor was it in standby.

So the mains power was hastily terminated and we looked, or sniffed for, the culprit. Turned out to be the Freeview box, which was hot to the touch around where the mains cable entered the unit (no external PSU). Lo and behold, when opened up, I discovered a bulging cap in the PSU section and a destroyed (burnt out and deformed) diode next to it, with the general area scorched as well. Looked like one of the bridge rec diodes (mains side) but unsure as 2 of the 4 diodes I could see were smaller which I haven't encountered before in a bridge rectifier. Transformer looked okay visually. Pretty nasty stuff.

Bulging caps are everywhere - in my job I've re-capped a fair few power sections of various audio mixing consoles - you start getting noise on the audio signal paths which is a dead giveaway. Also seen it on plenty of motherboards, hi-fi gear etc. All recent equipment too - theories of industrial espionage amongst capacitor manufacturers are rife.

[sevenlayermuddle]

I have dismantled 3 different freeview boxes for 'post mortem' after their demise, in each case the problem has been as described by Neilius, a blown capacitor had shorted leading to other components in the crude PSU blowing up (literally, sometimes).

Now I know that these cap's have a finite life, even if left on the shelf, and often have a manufacturer's stated life of less than a year at rated temperature.  So maybe the attrition rate just has be be accepted, and that the equipment has built in obsolescence.

What I don't get is why it's only this past decade or two it's become such a big issue?   I rescued my  Mum&Dads old 1963 Phillips transistor radio recently.  The PCBs are littered with electrolytics, all of which look fine, and the radio works perfectly. 

[guest]

Never had any problems myself (got a couple here from 2007/2008) but I've always mounted them vertically with the provided stand.

[sevenlayermuddle]

Never had any problems myself (got a couple here from 2007/2008) but I've always mounted them vertically with the provided stand.

Mine are also mounted vertically but admittedly they are
(a) mounted on a high shelf, with only about 3 inches clearance from ceiling. 
and
(b) side by side (router and switch), at the end of the shelf against a wall.

Both these factors will combine, I'm sure, to increase temperature.

The switch failure was the most annoying because it wasn't absolute, the ethernet error rates simple became phenomenally high so that low traffic activities (such as web browsing) were still OK, just needed a lot of retransmissions, whereas high traffic activities just saturated the LAN with duff packets without actually getting any significant throughput.  I should have twigged quicker, but it took me an embarrassingly long time (several days ) to figure out why my attempts to play DVDs over the network kept stalling.  That one I actually repaired with new caps though, and I still feel smug about it.   

[guest]

Apart from an old Shuttle PSU I haven't seen dodgy caps (ie fake) in maybe 5 years?

Perhaps I lead a sheltered life

Then again perhaps not as I try to run things as cool as possible, so could be people "stacking" stuff.