Question Strange Degrading Network Adapter

mindless1

Diamond Member
Aug 11, 2001
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Have a motherboard with integrated Realtek Gb, RTL8111GR.

First observed symptom was only getting 100Mb through it, figured cable damage and checked the port status lights and one was red. Unplugged cable, plugged back in, went to orange again. Switch at the other end shows GbE connection.

Yesterday started getting flaky, disconnecting for a few seconds at a time, then today, more and more often, for longer and longer. The system was not updated, windows updates turned off. System was rebooted a few times, different switch ports, still continued to get worse.

It's on a long(ish) (but not too long, 40M which has worked fine for years) ethernet run through two walls, so before cable swapping I thought I'd try installing a newer driver.

The newer driver enabled Realtek's current diagnostic to work, showed nothing wrong including the cable test. After barely staying connected earlier today, now seems rock solid *so far* again.

Anyone ever seen something like this? I could understand some kind of filesystem corruption but seems very odd to have it slowly get worse and worse over the span of a day, through reboots too, and the system in question shows no other evidence of filesystem corruption.
 

mindless1

Diamond Member
Aug 11, 2001
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Ignore the solution in my prior post, was stable for hours but then started disconnecting again. I'm leaning towards it being the AC/DC adapter for the switch, that the switch is getting dirty power and can't stay stable under much load.

Swapped in a different switch/adapter combo and if it continues to work, will autopsy old AC/DC adapter, and/or try old switch with new adapter.

Heh, this 15 year old Netgear GS105 switch has a lifetime warranty but the power adapter, only two years. I've probably replaced the power adapter a time or two already. Analyzing the switch, I did upgrade/replace the caps in it already.
 
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mindless1

Diamond Member
Aug 11, 2001
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Autopsy of faulty AC/DC adapter reveals a failed low side Capxon KF series, 25V, 470uF failed. I put the old switch back into service, is working fine with a different AC/DC adapter.

Replaced it with a Panasonic FS1C122, 16V, 1200uF (what I had in stock that fit, original Capxon KF was 10mm dia x 16mm height, Panasonic is 10mm dia x 17.5mm height, max that will fit due to casing clearance limit). I need to stock up on shorter caps!

Funny thing is, rummaging through my box of wall warts, had another of the same Netgear (p/n 332-10006-01) adapters fail previously, replaced the cap as I've just done in this one, then a few years later the high side, Capxon KM series, 22uF, 200V cap failed. Oh well, a few more years by replacing a 50 cent capacitor isn't all that bad.

Capacitors!!!!!!!!!!!!!!!!!! Nothing else matters much if they fail first. Well there is ventilation, I put the wall wart shell on a drill press and made swiss cheese out of it so it's no longer an EZ-Bake oven.
 
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mindless1

Diamond Member
Aug 11, 2001
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Capxon!!!! Was doing series upgrades/movement of routers today, noticed ANOTHER AC/DC wall wart has a faulty Capxon, high-side capacitor. It just hadn't gotten bad enough to crash the router yet.

I had already repaired that PSU once, years ago, even drilled vent holes in the casing so it was cooler running, but it was not enough to overcome the evil known as Crapxon.

On a related note, the AC/DC adapters I linked in my other topic about wall warts, are back on sale again. Still seems like cheapest delivered price if you buy more than two, to offset ~$9 S/H:


I can't guarantee they don't have crapxon in them, but at 4 bucks a pop, might be better to just buy a bunch than bother with it. ;)
 
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