bump

What kind of internet do you have?

Coaxial Cable (Docsis)

http://litramfg.com/wp-content/uploads/2013/09/coaxial-cable-assemblies.jpg

DSL / Phone line (ADSL, VDSL, Dial up, Bonded DSL, G.DMT)

http://www.plus.net/images/support/broadband/hardware/dlink320b/dsl320b_microfilter.jpg

This picture has a filter for the DSL/Landline Phone line but basically it's a narrow ethernet cable

Ethernet Cable (If you have a ethernet cable from wall to router, you probably have Fiber or some other Ethernet provided equipment such as Hatteras)

http://images.wisegeek.com/ethernet-cable.jpg

Considering that you're using ethernet I doubt it's the wifi itself. If you get high ping "especially when someone opens youtube" it sound more like a network load problem.
Have done a speedtest before and after the line went down?
Have you tried loading a youtube video on your pc or another pc connected via ethernet while playing? If the same happens it's definitely a network load issue.

Did you switch routers? Turn on Quality of Service on the new router and yes, mess with some settings.

That sounds exactly like a network load problem. What's your connection speed?

If it is people eating all your bandwidth your best bet is QoS, though even then it will probably not be as great as having no one using your connection at the same time.

@Comanglia

I use phone line (ADSL) and Ethernet Cable plugged in router and the case.

My network card is Marvell Yukon 88E056 PCI-E Gigabit Ethernet Controller.
This is how my router is set up, I only use the phone with the wire in the phone line. (sorry I only have this in french)

http://www.iam.ma/Particuliers/PublishingImages/maroc-telecom_routeur-Sagem-F@st-3304_Comment-brancher-mon-routeur_1.png

@Setsul
My downstream is 8mpbs, before the line cut I was getting 6.90-7.30 mbps, now after that I only get 6.50-6.90 mbps, even with wifi deactivated and me opening nothing.

I just did 3 speedtests, the server is from Chiclana, Spain.
•With wifi deactivated and youtube not opened :
60-80 ms, 6.80-6.90 mbps
•With wifi deactivated and youtube loading video :
100 - 140 ms, 4.50-5 mbps
•With Wifi activated and a pc using wireless connection loading youtube :
+150 ms, 3-4 mbps

That's interesting, and scary at the same time.

@Shun My router has a weird away of implementing QoS, I have sagem f@st3304-v2, and I only see the QoS options on the firewall's advanced filtering options. 1 l 2

Isn't there anyway I can prioritize my bandwidth over others ? before I had no problem when other people was using wireless connection, after the phone cut I never was able to get 7 mbps, maybe a new router would help ?

Pretty exactly much what I expected. I think QoS is your best bet, too.
There's two ways to set it up quick and dirty, just to see if it works:
1. Prioritise all UDP traffic (games are almost always UDP, bandwidth heavy stuff like youtube is TCP):

• Source Adress: Any
  
• Destination Adress: Any
  
• Protocol: UDP
  
• Operation: QoS
  
• QoS Operation: Set Priority

2. Prioritise all traffic from your PC:

• Source Adress: [Your Adress]
  
• Destination Adress: Any
  
• Protocol: Any
  
• Operation: QoS
  
• QoS Operation: Set Priority

I have the same problem since my sister watchs alot of series, so i wanna do that, but i don't really know what to to with this, i mean where do i type it ? I thought this had to be done on the router

Alot of what setsul said.

I'd like to add that it's extremely important to cap your upstream bandwidth when doing QoS at somewhere around 512K - 768Kbps if you have DSL. Otherwise if you cap out your upstream bandwidth you'll be completely dropped or have 500+ms pings.

Also out of curiosity could you show me the statistics page?

Example of what info I'm looking for.

Service State In Service
Line Status Up
Rate Mode Adapt at startup
DMT Standard 992.5A (ADSL2+ over POTS)
CPE Vendor (ver )
Up Time 515196 sec

-------------------------Downstream-------Upstream
Line Rate-----------6016 kbps-----------763 kbps
Margin---------------27.5 dB---------------13.5 dB
Power---------------19.1 dBm-------------11.4 dBm
Attenuation-------25.0 dB----------------13.6 dB
MaxAttainRate---19316 kbps ----------1028 kbps
Actual Delay------0.0 ms-----------------0.0 ms
Actual INP---------0.00 sym-------------0.00 sym

#9
Yes it's done by the router.
As to where, usually in the web interface. OP linked a picture of his so my instructions are based on that. On your router it'll probably look different.
Both the manual and google should be able to tell you if your router supports QoS and how to set it up.

@Comanglia
Network View I Wireless I Mac Filter (The action button only lets you type the mac address)
Basic Menu
LAN servers
Advanced Settings
Firewall
General I DMZ Host I Advanced Filtering
Network
DHCP relay configuration I DNS & default gateway configuration I Routing I Dynamic DNS
Statistics
ADSL Statistics I DHCP Statistics I Interfaces I Traffic

@Setsul
Shall I put those settings in both input and output ?
http://puu.sh/jRHiU/5fc0c949cd.png

Your QoS implementation looks really weird compared to the how it's done in DD-WRT and Tomato, so I'm not sure if I can really give you any advice.

I can tell you though, that you'll need to tweak how much of a cap you put on your outbound bandwidth as that has pretty much the biggest influence on how much data gets sent back to you. Set an upload limit that's about 80% of the highest upload speed you get and then see if other people using Youtube or other things significantly affects your ping. If needed, change the limit ti 70%

I'll consider that after I try Setsul's method, one question though, could I (in the future) get a new router (D-Link, for example) that is not licensed by my ISP ? I doubt that's the best word to describe it but my router here has the "Maroc Telecom" logo, so can I use any router and still everything would work ?

You generally can, but you'll have to know how to configure it.

wow, I've just noticed these protocols, one has ping in it. http://puu.sh/jSatZ/93cd21a7fd.png
Does that help ?

EDIT: I've just played with the advanced filtering settings, gave LAN ethernet a high priority while lowering Wireless Rules in both input and output, when I played tf2 I had like one or two spikes but ping was average of 90-100 ms at the time, which is great.

Are there any more stuff I could edit ?

Alright so, a lot of things.

1. You should speak with your ISP again to see if you can be put onto Line Path "Fast" instead of "Interleave" (should lower you ping times anywhere from 5ms-25ms)

https://en.wikipedia.org/wiki/Asymmetric_digital_subscriber_line#Interleaving_and_fastpath

2. You can get better speeds with the line you have upon switching from interleave, but this dependent on what your ISP is willing to sell and how much you're willing to pay.

3. When setting up QoS cap your upstream to 512Kbps

also don't change the protocols.