I'm experiencing a weird problem with some of my wireless laptops. We recently upgraded our internet connection to a faster one.
When I checked the speed on my dell inspiron 9400, everything checked out ok. When I checked it out on a Dell inspiron 6400 my speed was a third of what I got on the original. The strange this is that both have the exact same wireless card (an intel pro 3945abg with the same hardware revision).
Both machines have the same processor, windows version and have the same patches applied. Both have the same version of the driver and both drivers are configured identically. Both machines are sitting side by side, so signal strength is the same.
I don't any reason why the download speeds should be different, but they are.
As one last curious note, the upload seems to be the same on both, so it's only the download speed that is affected.
If anyone has any ideas, they would be greatly appreciated. Thanks in advance.
Obviously they don't have the same firmware/rom.... Sure it was a third instead of 2/3? I was working on a theory of multiplying the speed by the model number to get a "fudge" factor... So much for that theory... :(
What model access point or wirless router was used in the test?
How are you measuring the performance? From the internet or from a wired ethernet connected local server on your LAN? Using what software to benchmark the system.
How about some numbers instead of generalities on the speeds? I've seen far too many bits versus bytes errors.
Is that the version supplied by Dell or the update downloaded from the Intel web site? Are you using Proset to manage the connection or Windoze Wireless Zero Config? If Proset, have you looked at the diagnostics tab? |
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What processor?
What version?
Critical updates only, or did you include the optional updates and hardware updates?
What version of the driver?
Are they simultaneously downloading up updateing while you're not watching? Having two machines next to each other is not a great way to do benchmarking. Turn one of them OFF or disable the wireless adapter when running benchmarks. If one machine was furiously downloading Windoze updates, while you were running benchmarks on the other, I can see there might be a substantial slowdown.
I don't see any numbers.
What upload speed?
Without numbers, there's no way to do a sanity check on your observations and allegations.
First off, although I appreciate all your suggestions, none of them are relevant. I doesn't matter what processor or anything else is in the machines. They are identically configued except the 9400 has a bigger screen and better video card which would have no bearing on my problem. The rom/firmware version is the same for the wireless card, I've checked. The driver is the same, I installed it to be so.
They are accessing the same access point so the model and revision of the AP doesn't make any difference. It is not a bit/byte error because that wouldn't be a third now would it? It'd be more like an 1/8 (not exactly I know).
And as for software to test, it doesn't matter. It's the same software on both machines. Now that we've gotten all the little details out of the way I'll repeat the original question.
Does anybody know of a reason why two identically configured machines would have different wireless download on a consistant basis from the AP regardless of whether they are both accessing the AP at the same time or not. There is no difference in the machines despite what your hunch may be, I've spent two days getting every driver, firmware, MS patch to be equal on both machines. The problem is limited only to the wireless connection and is completely repeatable.
Sorry if I sound sore about the whole th> snipped-for-privacy@gmail.com hath wroth:
The reason I ask for numbers and methodology is that there are a substantial number of errors that can be attributed to arithmetic and proceedural errors. My basic proceedure is to isolate the potential culprits by elimination or replacement. That's a bit difficult to do without some clue as to what you're working with, what your doing, and what you're getting. For example, setting your unspecified access point to a fixed speed instead of automatic has a big effect on performance in the presence of interference. Turning OFF the 802.11b compatibility feature is another. Disarming the Super-G and Afterburner functions seems to also change performance somewhat.
I'll be blunt...(when am I not blunt?). It's difficult enough to deduce the cause of a problem without additional handicaps. Some benchmarking methodologies return useless numbers. For example, using Firefox to download and save a file from the internet results in numbers that are affected by the time delay between when the download starts, and when the user elects to hit the "save" button. Other benchmarks are severely affected by local cacheing. I recommend IPerf:
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Sure. I can think of lots of reasons. One of my friends calls me up and declared his new wireless laptop to be slow dog. Two hours later, he calls to inform me that it magically has fixed itself and is now running at normal speed. The Windoze background downloader was merrily filling his DSL pipe with updates without the slightest indication on the screen. Needless to say, it was slow during the updates.
You seem to be making a substantial number of assumptions. Have you ever considered testing your assumptions? For example, have you considered swapping "identical" Intel 3945abg cards? Have you consider dragging the slow laptop over to another access point and seeing if the problem persists? If it doesn't, then there's some incompatibility or settings problem between the access point and laptop.
Just answer one question (for my amusement). Are you using Intel's Proset utilities to manage the wireless or are you using whatever Dell supplied?
Yep. I've noticed that if I make the same mistake over and over, it usually results in the same problem, over and over. Check your assumptions.
That would be an undestatement. I presume you've also called Dell support to vent your frustrations. They might have a BIOS update for the 9400 that will magically fix things. That's what happened to me with an older Dell 5150 laptop and the 2200bg card. It was doing weird things. Replacing the card and screwing around with Windoze did nothing. I had the latest BIOS installed, but the product had just been released and I thought it might be worth a call. Apparently, they were working on the exact problem and sent me a beta BIOS image. It worked.
I kinda like reading Sherlock Holmes mysteries. One of stories had a line something like "When you have eliminated the impossible, whatever remains, however improbable, must be the truth." If you can't point directly at the problem, take the time to eliminate what is NOT the problem. For example, replace the access point and see if there's a differnce. Swap the wireless cards. Take the laptop to a different location to reduce interference problems. Try different drivers (Proset versus WZC).
That which is most obviously correct, beyond all need of checking, is usually the problem. Check your assumptions.
You keep asserting that the machines software is equal.... THEY ARE NOT!!!!!!!!!!!!!!!!!!!!!! If you claim to know anything about computers, you know there is a BIOS, and they are never ever ever the same between different models/years of a machine....
Try what jeff suggests and see if there is a BIOS update... What's that? BIOS? .... Hey it's software and is not the same between your two machines!
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