Lagspikes, issue most likely on my end, but I can't find its source:(

WinMTR

Specification:

Cpu: i3 4130
Gpu: AMD HD7870 Pitcairn, no OC
Ram: 8Gb 1333Mhz
Wi-fi adapter TP-Link TL-WN725N v2 paired with 3 meters (3 yards 1 feet) USB extension, which made it better (honestly at some point I had some 28.8 kbps tier internet. Or at least it used to behave alike.)
OS: Windows 7 Home Premium 64bit

Graphics drivers up to date. Windows isn't pirated. Wi-fi isn't stolen, but I have few thick walls to where modem works and it must stay like this. I run least possible graphic settings (and I'm ok with this, too). My PoE isn't Steam relase.

I had quite some issues with wi-fi adapters drivers- most recent doesn't work properly; Windows pick almost the oldest ones if I let it pick itself, out of all drivers ever relased for w7 from TP-Link home page; still, only that old ones works more or less properly. The newest makes my Wi-fi signal exccelent, but they either crash at all after 15 minutes of work and refuse to work again (at all, I need to reinstall them) or reset the device every 15 minutes. I unistalled all tp-link software, drivers included and reinstalled it in every possible configuration- with firmware utility, without firmware utility and so on. Also, I spot info that this model is known for causing troubles when I was googling for solution.
Other symptoms: daytime is the worst, but even nights aren't that much better lately(they use to be fine). InSSIDer says this(I use FunBox-89C2 connection):
For few reasons I won't be able to mess with modems setup at all, tho. Also I can't and won't be able to switch to ethernet cable. I've been playing diablo 3 for last few months, connection wasn't, well, as crappy (still far from good). It was playable in contrary to my PoE. That gives me bit of hope that I'll be fine by downloading some *.dll, turning some service on/off or such.



I have netis WF2411i router lying around, but I failed with its configuration so far (can't make it into client mode). Frankly tho, I didn't try it very hard yet. Any ideas, tips, directions to where I may find my solution would be most appreaciated.
I'd like to avoid reinstalling windows, I have no dvd-rom on me and buying one would hurt my budget atm (despite how cheap they are, my budget is very ill now, need to rest).

Thanks in advance. I'll provide any other neccessary data if needed.

Edit: And once again downloading Steam version fixes issues for both relases. I'd love to know what the hell did I actually do, but as long as it works I won't complain (too loud).

Whatever black magic it was, downloading steam client helped. For both clients...that's 2nd time it fixes poe for me. I have no idea what was the case but I think steam client must have downloaded some crucial stuff, or messed with services or firewall setup or something totaly else. I have no idea, honestly. Ping is steady 65, which I find superb (I have 80 at best usualy).