HolidayBuyer's Guide

Computer Help forum


Why does our wireless router slow down my download speed.

by m coste / August 9, 2013 8:28 AM PDT

Hi all,
Ok this may be a common problem. So I hope someone can tell me why this happens.
I do get 15mb/s to 16mb/s download speed from my provider. (I run However about once a month the download drops to 3mb/s or less.
Getting advice from my provider I reset my modem and router. Voila' problem was instantly solved.
Now the next time the download/upload dropped to almost nothing I unplugged the router for a few seconds. Plugged it back in and the speeds were back where they belong.
I would like to know why my router "clogs" up over time. Is it time to get a new wireless router?

Discussion is locked
You are posting a reply to: Why does our wireless router slow down my download speed.
The posting of advertisements, profanity, or personal attacks is prohibited. Please refer to our CNET Forums policies for details. All submitted content is subject to our Terms of Use.
Track this discussion and email me when there are updates

If you're asking for technical help, please be sure to include all your system info, including operating system, model number, and any other specifics related to the problem. Also please exercise your best judgment when posting in the forums--revealing personal information such as your e-mail address, telephone number, and address is not recommended.

You are reporting the following post: Why does our wireless router slow down my download speed.
This post has been flagged and will be reviewed by our staff. Thank you for helping us maintain CNET's great community.
Sorry, there was a problem flagging this post. Please try again now or at a later time.
If you believe this post is offensive or violates the CNET Forums' Usage policies, you can report it below (this will not automatically remove the post). Once reported, our moderators will be notified and the post will be reviewed.

All Answers

Collapse -
I get the...
by Dafydd Forum moderator / August 9, 2013 8:35 AM PDT

same thing. I just unplug for a minute turn back on and voila. Don't know why but I'm sure it's fairly common.


Collapse -
Just a thought.
by Dafydd Forum moderator / August 9, 2013 8:55 AM PDT
In reply to: I get the...

Are you using any P2P file sharing software? I don't but I had to ask.


Collapse -
Router slow down
by m coste / August 11, 2013 2:19 PM PDT
In reply to: Just a thought.

No P2P file sharing.


Collapse -
When mine does that, I get a new router
by wpgwpg / August 9, 2013 9:39 AM PDT

When mine does that, I get a new router, and the problem goes away for 2,3 years. You'd think something with no moving parts wouldn't wear out, but they do. The good news is that they're cheap. I bought my Tenda wireless-N for $15.

Collapse -
Check for firmware update
by Bob_Meyer / August 9, 2013 10:29 AM PDT

That really sounds like a memory leak in your firmware. Google the router make and model + "problem" and see what you find. There may be a firmware upgrade for your model on the manufacturer's website.


Collapse -
The answer
by Jimmy Greystone / August 9, 2013 10:47 AM PDT

The answer is rather involved and technical, there's also generally very little the average person is going to be able to do about it.

Most routers run some embedded form of Linux, but the company making the router doesn't bother to change a lot of the default settings that were intended for desktop systems, not embedded platforms with hard resource limits. So every single site you visit creates a new connection log on the router, for no real particular reason since the user can't access it. That log is then maintained for several days or even weeks until eventually your router runs out of memory. On a desktop, the system could just use swap space and keep going, but routers don't have a HDD or any other kind of storage to use for this purpose, so you get a condition known as thrashing. Think of it like someone whose hands are full and is trying to say open a door. It's clear they'll have to set something down to do it, but there's nowhere to set anything down, so they're stuck.

To make things even more fun, in an effort to reduce production costs, many router makers reduce the amount of RAM in the router. Some have as little as 2MB, which is barely enough to run the core services. This is why you see things like the old revision Linksys WRT54GS going on ebay for ridiculous sums of money. It had 16MB of RAM whereas most routers have 8MB or less.

The only fix is to either reboot the router and forcibly clear the RAM or void the warranty on the router and install a custom firmware, assuming there is one that supports your router. DD-WRT has the broadest support for devices, but there are a couple of others like Tomato for a narrow range of routers. Custom firmwares have generally sanitized the settings for routers.

Collapse -
Wireless router slow down.
by m coste / August 11, 2013 5:14 AM PDT
In reply to: The answer

Thanks. Makes sense that router memory will become full. With no ability to use a swap file of course there is no room in the memory over time.
I'll just periodically unplug it and empty the memory. It is not a big deal to do this. It takes less than 30 seconds.

Popular Forums
Computer Newbies 10,686 discussions
Computer Help 54,365 discussions
Laptops 21,181 discussions
Networking & Wireless 16,313 discussions
Phones 17,137 discussions
Security 31,287 discussions
TVs & Home Theaters 22,101 discussions
Windows 7 8,164 discussions
Windows 10 2,657 discussions

The Samsung RF23M8090SG

One of the best French door fridges we've tested

A good-looking fridge with useful features like an auto-filling water pitcher and a temperature-adjustable "FlexZone" drawer. It was a near-flawless performer in our cooling tests.