Make and model of computer... Operating system used? And operating system used on the laptop? Have you used registry cleaners/optimizers on your computer because such usage can sometimes cause these issues? Anything else? More than one antivirus installed?. Are you running any Torrent programs or sharing programs? If Windows 10, have you turned OFF the setting to share its Windows Updates with other comps on the network? The more information you give us, the better informed our answer will be.
If the above suggestion don't help with the ping issue, a couple of things come to mind. First, and the quickest thing to check is to check the ethernet card manufacturer's website and see if there are any updated drivers for your card that are supported on your operating system. Next, if you haven't checked lately, click on the link below and follow the steps, in the order given, to check for malware that could be causing network traffic.
“Expand” the post titled: "Please try this" at the link below:
http://www.cnet.com/forums/post/f742c795-5881-433b-a29b-6d758efe5cd3/
Hope this helps.
Grif
For a couple of weeks my ping has started growing to 200 ms for a couple of minutes (usually 30 min or more). This started happening more often and is annoying as I am sometimes playnig online video games and low ping is a must. I tried pinging from my laptop and it didn't work. However, i unplugged my computer from the Internet and the laptop worked fine with 50 ms. I figured it should be a cable problem so i used another cable which i first tested on my laptop and it worked, then i connected it from the router to my computer. Same ping of 200ms. Anyone can please help me?

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