Wireless N problem XPS 15

Hello all. I've been browsing this website as an unregistered user for some time now (from my phone until my new laptop arrived).

I have an XPS 15 L502X. Core i5-2520M, 8GB RAM, 2GB nVidia GT 540m, Intel 6230 Advanced-N.

My problem is with Wireless N, I don't get a solid connection without disabling it. I have a clean install of Windows 7 x64 Ultimate. I've tried the latest drivers, from both Intel's Website and Dell's. All Power Settings in all Profiles has been set to Maximum Performance. Firmware on router (WRT120N) has been updated to the latest. I've read plenty of threads online about this and tried as many of the "answers" as possible, and still cannot get a good quality connection. As soon as I disable N, the speed in my network status goes from 150mbps to 54mbps. The network is then absolutely stable. All the other devices that connect to the router are either hardwired or connecting at Wireless-N. One Dell Studio laptop with 7 x64 and an Intel 6000 wireless card, connects flawlessly. The only thing I can see being the cause is something I read about called Power Save Polling. There is a guide on Intel's website detailing how to put the card into Continuously Aware Mode, which is a much more acceptable solution than using G. The problem is, they describe the use of a program (The Intel Wireless Connection Manager) or Control Panel Settings, but I can't find any of these things on my computer or from Intel's website.

Using speedtest on N most often results in latency failure, but the downstream speed is much higher (while it lasts) then the G connection (which is always stable). Downloading files is much quicker on N, but rarely finishes before the connection cuts.

I've tried everything I can think of to fix this problem. Anyone got any other solutions?

 

Some thoughts...

Can you switch channels in the router?

Is the router wireless configured for N-mode only?

What is your WLAN environment... single family residential?

Have you reseated the card and its antennae connections?

Could be the adapter just fails at higher speeds.

GK

 

The option to change channel numbers appears to be greyed out in the router configuration, but the channel width is set to Auto (can choose 20MHz or 40MHz).

The router has been set to 'Mixed' the entire time. I guess since all the wireless clients support N, I've changed it to N-only to see what happens.

Single family home, this unit is on second story directly above router. Speed is unchanged closer. Other laptop is a Studio 15 and desktop, a Dell also, not sure how old, but it's hardwired, as is the laptop (unless it's off it's desk). I haven't played with the card yet. I suppose it's not out of my league, I can easily assemble a tower and make all necessary connections, and I've seen where the card is, how to access it, etc. I'll try that as well and report back.

UPDATE: Ran a speed test with the router set at N-Only... Speed while router is on mixed, n enabled on card about 19-20mbps. N disabled, about 13-15. N-only on router with N-enabled on card... 1.27 mbps.

Card and antennas reseated, speed test showed average considering settings, upload test failed (usually occurs when N is enabled on card).

 

Given that the other notebook maintains satisfactory N performance in the same environment, it could be that the XPS wireless adapter is just not healthy. It should not take any special driver setup to make it work well enough on your WLAN with your security settings. And it is new... a candidate for failure. So, I would ask Dell to replace it.... explain everything you've tried and that you have another N unit workling just fine on the same router.

GK

 

I'd rather see if there's a software solution available as I seem to not be the only one. I've done a full network reset, cable modem first, then router (reset to factory defaults and reset all necessary security settings), then the computer got the drivers and Intel software deleted, and reinstalled upon reboot (drivers only, no Intel software). Then let the router see the modem, and the computer see the router (setup using WiFi Protected Setup this time).

So far so good.. we'll see the real test when I get a chance to test out a Skype call.

 

I can confirm that the problem has not returned upon a full network reset of the router and the affected machine.

This thread can be closed.

 

Just wondering what wireless router you have? Also, keep an eye out for reoccurances. Could be the router and the wireless card just don't quite get along.

 

It's a WRT120N, which upon a little research should only be reaching speeds of 130mbps, so it's not even 'fully' N.

 

It appears as though the entry-level hardware combined with entry-level firmware create a frustrating experience for users of the WRT120N. Amazon.com: Customer Reviews: Cisco-Linksys WRT120N Wireless-N Home Router

To be clear, though, it is either using the 802.11n standard, or it isn't. If you're achieving link speeds greater than 54mbps (~25mbps throughput - more on that in just a second), then it's on wireless-n utilizing MIMO antennae. Wireless speeds are something of a marketing misconception.

The problem is that in a wired environment, there are two pairs of wires communicating - two for up, two for down - all occurring simultaneously. So on a 1gbps wired network, you get a full 1gbps up, and a full 1gbps down. In wireless networks, each antenna's connection is half-duplex, meaning it either gets to transmit or receive at any given point in time - not both. With the introduction of 802.11n, MIMO (multiple in, multiple out) antennae for wireless were standardized. To achieve greater than 54mbps, given the current frequencies, restrictions, and frame-types, you must use a MIMO antenna, which is still limited in that it is still half-duplex, but can side-step that issue somewhat via multiplexing, i.e. tuning to two different frequencies simultaneously, allowing for a large increase in throughput - numerically, about 154mbps in half-duplex, which would read as about 70-75mbps down and 70-75mbps up in an ideal environment with little overhead.

 

Can anyone help me out? I'm having the same issue and have thus far been unable to fix it. My Advanced N card is lagging uncontrollably in an online gaming environment and speedtest.net is telling my my download speed is .7MBPS =(