2 PC's - 2 different download speeds

[PortyAL]

Hi

I've 2 laptops on my wireless (b) home network. One is a Dell Inspiron 510m and the other is a Dell Inspiron 2200. Both have the same spec (1300Mhz, 40Gb HDD, 512mb RAM)and have the same firewall (Zonealarm).

Speed tests on

http://www.mybroadbandspeeed.co.uk,

have showed that my download speed on the 2200 almost double than that on the 510m. A test today gave a speed of 2.8mbps on the 2200 and 1.5mbps on the 510m. The 2 PC's were sitting side by side at the time.

Any theories as to why there would be a difference would be greatly appreciated.

Thanks

AL

 

[mainegeek]

PortyAL,
It could be from several factors.

"I've 2 laptops on my wireless (b) home network"
Why (b)? and is it set to B only or mixed?
Are both laptops set to B/G mixed?

Both laptops support G though I believe they use different wireless chipsets.

 

[PortyAL]

Hi

The 510m only supports "b". The 2200 supports "b" and "g" and is my sisters laptop which I was installing software on. I wouldn't normally have it so that's why I've only discovered the difference now. I have a Linksys WAP11 access point which only supports "b".

Thanks

AL

 

[mainegeek]

according to the specs for the 510m it has triple band 802.11 wifi A/B/G with.

The 510m is probably going through the B access point or is configured for B only instead of B/G mixed?

 

[kmcferrin]

The CPU and memory specs don't have anything to do with download speeds. Contrary to what Intel wanted people to believe when they were advertising their "Netburst" CPUs, your download speed will be governed primarily by your networking hardware.

Do both laptops have the same chipset for their network adapter? If not, once could be faster than the other. Probably not, since one is 'b' and the other is 'b/g'.

If they do, are they using the same driver? If not, one of the drivers may be less optimized or buggy.

Are they running the same OS? The TCP/IP stack on newer versions of Windows is usually much faster than on older versions. The stack also tends to be better optimized on Linux distributions than on Windows.

Also, keep in mind that wireless ethernet is shared media (more like a hub than a switch) and that interference from other RF devices (or even shielding) can play a role.

Finally, keep in mind that those broadband speed tests are only general guidelines. The Internet is dynamic, and those web sites only show you a snapshot of one moment in time.

 

[cdogg]

An important point to consider is that 'B' goes up to 12Mbps (or 1.5 MB/s), which is plenty fast for any broadband connection out there.

So the increase in speed that you would get going with 'G' or 'N' shouldn't matter.

I suspect that although the two laptops have similar hardware specs, Windows running on the 510m might have a clogged registry and/or too many processes in the background. It could also have an underperforming hard drive. There are a lot of factors at play. I suspect that a fresh load of Windows would make a difference (without installing any 3rd party apps such as Zonealarm).

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[BadBigBen]

other things that maybe involved are:

MTU, MSS, Default TCP Receive Window (RWIN)...

to find out the diffs between the two, go to SpeedGuide.net

http://www.speedguide.net/analyzer.php

Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."

 

[ceh4702]

Well on a laptop the NIC is integrated or not. So the integrated part does depend on things like shared memory, chipset for the NIC, the actual cable or wireless connection. Wireless has to be coming in through some chip or interface card or usb wireless device. All of this uses shared resources or some interface hooked into some kind of port that goes through the motherboard.

On wireless not all antenna's are created equally. Some receive and transmit better than others.

If you do not like my post feel free to point out your opinion or my errors.

 

[PortyAL]

Thanks for all your advice.

The "underperforming hard drive" theory could have something to do with it. The drive "clicks" every now and then (something it's done since I got it nearly 2 years ago). As the machine in general has never given any problems, I never pursued the issue.

I'll also wiring the laptop into my router this evening to see if that makes a difference.

Thanks

AL

 

[kmcferrin]

Well on a laptop the NIC is integrated or not. So the integrated part does depend on things like shared memory, chipset for the NIC, the actual cable or wireless connection. Wireless has to be coming in through some chip or interface card or usb wireless device. All of this uses shared resources or some interface hooked into some kind of port that goes through the motherboard.

Integrated graphics processors usually share system memory, and some sound chips (that are not integrated into the chipset, but are included on the mainboard) will do software-based processing on the host CPU, but that's not usually the case with NICs.

 

[PortyAL]

I've confirmed that the problem lies with the wireless adapter in the 510m. I wired the laptop to my router and got a download speed of 2.9mbps. I disconnected and reconnected via the WAP and got a speed of 1.5mbps.

I might try re-installing the network adapter or look for a newer driver to see if that helps.

 

[PortyAL]

Just for the record the wireless adapter in the 510m is an Intel(R) PRO/Wireless LAN 2100 3A Mini PCI Adapter.

AL

 

[PortyAL]

Further update-

Downloaded and installed the latest driver from the Dell website. It made no difference.

 

[cdogg]

Does the speed improve when you set it near the router?

If not, then it might be worth adding a different USB or PCMCIA wireless adapter.

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884