# Old tablet have a wifi speed of 130mbps but my laptop is only getting 72.2mbps



## luthor (Apr 2, 2017)

Hi, please excuse my poor English as is not my first language. I'm having issues with my wifi connection. Currently, my s7 edge is running at 144mbps, old Surface RT running at 130mbps but my dell inspiron 14 5000 series 5459 and Oneplus 3 is only at 72.2mbps and the adapter Dell is using is Intel(R) Dual Band Wireless-AC 3160. Security type is already set as WPA2-Personal, Encryption type at AES.

I've tried going to Properties > Configure > Advanced tab and changing both 802.11 n channel width for band 5.2/2.4Ghz to Auto and 20mhz only, didn't change anything. Wireless mode is already set as 802.11a/b/g

Since my S7 and surface RT is already capable of running above 130mbps through wifi, shouldn't my Dell laptop and OP3 be able to run above 130mbps as well. Any advice will be greatly appreciated. Thanks all.


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## TheLostSwede (Apr 2, 2017)

To get 300Mbps you need to use 40MHz, otherwise the max is 150Mbps. 
You also need to use WPA2-PSK/AES to get 150/300Mbps, as TKIP doesn't allow for speeds above 72.2/144Mbps in 20/40MHz mode.
This might require changes to the Wi-Fi settings on your router as well.


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## Kursah (Apr 2, 2017)

For higher bandwidth on N channel you usually want 40MHz and on AC you want 80MHz iirc. This becomes more of a challenge in WiFi saturated areas.

What is the model of your wireless access point or wireless router?


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## Aquinus (Apr 2, 2017)

For the sake of clarify, often the reported wi-fi speed is the aggregate of both upstream and downstream bandwidth, not the maximum possible in any one direction. So saying 150Mbit might mean 75 up and 75 down and 300Mbit might mean 150 up and and 150 down. The wi-fi needs enough radios to run on multiple channels (MIMO,) and won't go much faster than 75Mbit up/down if it's 1x1.


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## TheLostSwede (Apr 2, 2017)

Aquinus said:


> For the sake of clarify, often the reported wi-fi speed is the aggregate of both upstream and downstream bandwidth, not the maximum possible in any one direction. So saying 150Mbit might mean 75 up and 75 down and 300Mbit might mean 150 up and and 150 down. The wi-fi needs enough radios to run on multiple channels (MIMO,) and won't go much faster than 75Mbit up/down if it's 1x1.



This is simply not true, please don't spread made up information like this.
1x1 means one transmit and one receive antenna and has nothing to do with MIMO for starters.
The reported speed is NEVER aggregated, but at the same time is not the actual speed either, it's the theoretical maximum speed. 65, 72.2, 144.4, 150, etc indicates a solid connection at the maximum speed of a 1x1 adapter depending on a few variables such as encryption standard and channel bandwidth used. 
See: https://en.m.wikipedia.org/wiki/IEEE_802.11n-2009


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## newtekie1 (Apr 2, 2017)

TheLostSwede said:


> This is simply not true, please don't spread made up information like this.
> 1x1 means one transmit and one receive antenna and has nothing to do with MIMO for starters.
> The reported speed is NEVER aggregated, but at the same time is not the actual speed either, it's the theoretical maximum speed. 65, 72.2, 144.4, 150, etc indicates a solid connection at the maximum speed of a 1x1 adapter depending on a few variables such as encryption standard and channel bandwidth used.
> See: https://en.m.wikipedia.org/wiki/IEEE_802.11n-2009



Actually, what he is talking about would duplexing, not MIMO.  The 1x1 is directly related to MIMO.  Anything rated 1x1 is not MIMO capable, as MIMO stands for Multi-In Multi-Out.  It uses multiple antennas to transmit in a direction at the same time.  So 2x2 would be MIMO, using 2 antennas to send at the same time, and two antennas to receive at the same time.  Effectively doubling the bandwidth you can send in each direction.

Now, to the OP's issue.  The Intel AC-3160 is a 1x1 wirless adapter.  This means it can only send and receive using one antenna.  With Wireless N, the maximum speed possible with a single antenna using 20MHz channel width is 72.2Mbps.  That is why the Dell Inspiron 14 is only getting a 72.2Mbps connection.  Raising the channel width to 40Mhz would double the connection to 144Mbps.

The Surface RT is able to get a higher connection speed because it uses a Marvell Avastar 2x2 Wireless N adapter.  This would allow a maximum of 144Mbps, but it is only getting a 130Mbps connection likely because of interference in the area causing the connection speed to step down.

Changing the channel width to 40MHz(likely the "Auto" setting in the OP's router) doesn't guarantee the devices will get a faster connection or use the 40MHz channel width.  A lot of times they just ignore the 40MHz channel width and still use use 20MHz.


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## Aquinus (Apr 2, 2017)

Thank you for the added clarity, @newtekie1. You were much more elegant with your response than I was with mine. @TheLostSwede, that's what i meant. 1x1 isn't MIMO, you're right because there is only one tx/rx pair but, more radios for RX or TX instantly makes it MIMO. Either way, my point was that the slower adapters are only 1x1 which is going to limit you to 20Mhz wide channels.


TheLostSwede said:


> The reported speed is NEVER aggregated, but at the same time is not the actual speed either, it's the theoretical maximum speed. 65, 72.2, 144.4, 150, etc indicates a solid connection at the maximum speed of a 1x1 adapter depending on a few variables such as encryption standard and channel bandwidth used.


Man, find me a 1x1 802.11n device that can actually recieve or transmit at 150Mbit and I'll believe you but, the reality is that the 802.11n spec only allows for a maximum of 72.2 for a single 20Mhz channel in any one direction. So if your 1x1 802.11n device is telling you "150Mbit," it's really saying 75 in each direction at best because you need 2x2 with 40Mhz channels to hit 150 in either direction.


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## newtekie1 (Apr 2, 2017)

Aquinus said:


> Either way, my point was that the slower adapters are only 1x1 which is going to limit you to 20Mhz wide channels.



The number of antennas doesn't determine the channel width.  The channel width is per antenna.  So a 1x1 can use 40MHz channel width and get speeds faster than 72Mbps.  Though the speed is usually 135Mbps because you have to have a very clean interference free signal to get the full 150Mbps.


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## TheLostSwede (Apr 3, 2017)

Normally you should set the channel width to 20/40 so you avoid interference with neighbours, but if there is none, you get the benefit of the 40MHz channel bandwidth.

There are plenty of 1x1 devices that can do 150Mbps over Wi-Fi, it's a configuration issue as to why people don't get the speed. However, some are limited to 65 or 72.2Mbps due to the modulation they support as per the Wikipedia link above.

Considering I spent 2.5 years working for a router manufacturer, I think I should have an idea about how these things work.

And having more than one antenna doesn't mean that you get MIMO automatically. Some devices have extra antennas to help improve the signal and they just appear to be MIMO for this, but you can't actually transmit more data streams using them. Then there's MISO, SIMO etc. that use an extra antenna one way, but not the other way. By looking at such a device, you wouldn't know if it's MIMO, MISO or SIMO, as they would all have two antennas.

The OP came here for advice on how to fix his problem, not to get "fake facts" which this thread has turned into.

Anyhow, I've added what I have to say.


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## remixedcat (Apr 5, 2017)

Tick the "antenna diversity" setting in the adapter settings. Try that of your router setting is fine


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