Comcast - Mac OS X 1/6th of PC DL speed

dandean · 10-23-2005, 01:59 PM

Hi,

I don't know if this has been asked before, so please excuse me if it has, but I can't seem to figure out what's going on with my cable modem speeds on the Mac and PC.

First, we were having some real difficulties with cable in the neighborhood, so Comcast sent a bunch of different people up to fix things. First, they repaired the rusted co-ax cable connections. This helped. Now they are about to replace the actual cable drop. This will probably help, too - I guess.

What I don't understand is that when I take the Speakeasy speed test http://www.speakeasy.net/speedtest/ on my iMac running Tiger 10.4.2 I get 1100-1200 kbps D/L and 350 kbps U/L. The U/L speed is at its capped max.

If I run the exact same test on my PC, the D/L speed is 6619 kbps and D/L is 357 kbps. This is what's advertised and what I'd expect.

What is this? Shouldn't he Mac speed be nearly the same as the PC speed instead of 1/6th of the DL?

My gear:
Linksys Cable Modem v4.0 (new) BEFCMU10 (supports docsys 2.0)
Netgear Rangemax Wireless router
Comcast Cable
I-Mac 1ghz with 10.4.2
PC w/ XP 1.8 ghz Pentium

Help...

Dan Dean

hayne · 10-23-2005, 03:06 PM

1) There have been a bunch of similar threads on these forums - so search and maybe you will find something helpful

2) Make sure you disconnect your PC from the network when you do this speed test on your Mac - just to make sure the PC isn't interfering somehow.

3) Plug your Mac's cable into the port on the router that was being used by your PC - that way you know that you are using a known good port.

4) You shouldn't trust the results of these speed tests - instead try downloading some big file from a site with good bandwidth (e.g. a QuickTime movie from the Apple movie trailers site) and compare the real-world download times. Do the test several times in different orders (PC vs Mac)

cwtnospam · 10-23-2005, 03:28 PM

Try putting the DNS server info that your router is using into the Mac's DNS server settings. I'm assuming you're using DHCP and System Preference->Network->DNS Servers is blank, and this can cause a delay.

Jay Carr · 10-23-2005, 03:35 PM

And have you tried Broadband Optimizer. Sometimes UNIX isn't completely optimized for high speed access. I got this link from Trevor a while ago, installed it, and things have picked up a bit.

http://www.enigmarelle.com/broadbandoptimizer.py

bobw · 10-24-2005, 11:59 AM

I had the same thing happening with a Mac and a PC with Comcast.

On the Mac I changed the Ethernet settings in Network PreferencePane;

Configure - Manually (Advanced)
Speed - 100baseTX
Duplex - full-duplex

Rebooted and had the same speeds as the PC. Doesn't work for everyone.

dandean · 10-24-2005, 12:13 PM

Thanks everyone for the tips. I've tried every one of them and have had no change in speed. My next door neighbor has a MAC w/ OS X and is having the same issue. Anything else I/we should try? Comcast says they are reading 7.1 mbps at the tap about 60 feet away. They are probably using a PC to read this speed.

Thank you!
Dan Dean

bobw · 10-24-2005, 12:28 PM

Shut everything down.
Boot the Modem -wait a few minutes
Boot the Router - wait a few minutes
Boot the Mac, check speed

cwtnospam · 10-24-2005, 01:32 PM

Comcast DNS servers have been flaky in the past. As a test, try using one of these:
4.2.2.1
4.2.2.2
4.2.2.3
4.2.2.4
4.2.2.5
4.2.2.6

hayne · 10-24-2005, 01:42 PM

Quote:

Originally Posted by dandean


	Thanks everyone for the tips. I've tried every one of them and have had no change in speed.

Please report an example of a real-world download time - e.g. (as I suggested earlier) one of the larger files from Apple's movie trailer site.

macosx4me · 10-30-2005, 08:29 AM

Hi. I just wanted to let you know that I used that same Speakeasy test with my AlBook (1.25 GHz) running 10.4.2 over 802.11g (Airport Extreme) which is connected directly to my Comcast cable-modem.

Result was: 6041 dl, 354 ul

With my PC (2.4 GHz P4, direct connection to the Airport Extreme's LAN port), I get 6165 dl, 349 ul.

Connecting my Mac to that same cable (used with the PC tower), the "Mac" results are nearly identical (6039 dl).

Please note that this site:
http://www.auditmypc.com/internet-speed-test.asp

stated my mac's dl speed to be 6793 Kbps !

I tested with some other speed-test services (google for: dsl speed test), choosing a server as close to me as possible. Got dl speeds of: 6129, as well as several lower speeds.

Other points of possible interest:

I did not use BroadbandOptimizer. I haven't restarted in a week (I sleep the unit instead), would be longer but I just did a RAM upgrade.

I've performed this test via a direct connection with an Asanté router and the results were similar.

I'm posting this to help clarify that there's nothing specific to 10.4.2 and Comcast that is the cause of your problem.

whodean · 11-07-2005, 10:03 AM

I have the same problem here, had an older Motorola Cable Modem and Comcast tech just replaced, he got 6mb dl on his win machine, but I still get 2-3mb dl on my powerbook with 10.4.3 (both with airport express and direct ethernet connection to the cable modem) , any other ideas?

10-30-2005, 08:29 AM	#10
macosx4me Prospect Join Date: Oct 2005 Posts: 4	Comcast w/ OS X, my results, same test. Hi. I just wanted to let you know that I used that same Speakeasy test with my AlBook (1.25 GHz) running 10.4.2 over 802.11g (Airport Extreme) which is connected directly to my Comcast cable-modem. Result was: 6041 dl, 354 ul With my PC (2.4 GHz P4, direct connection to the Airport Extreme's LAN port), I get 6165 dl, 349 ul. Connecting my Mac to that same cable (used with the PC tower), the "Mac" results are nearly identical (6039 dl). Please note that this site: http://www.auditmypc.com/internet-speed-test.asp stated my mac's dl speed to be 6793 Kbps ! I tested with some other speed-test services (google for: dsl speed test), choosing a server as close to me as possible. Got dl speeds of: 6129, as well as several lower speeds. Other points of possible interest: I did not use BroadbandOptimizer. I haven't restarted in a week (I sleep the unit instead), would be longer but I just did a RAM upgrade. I've performed this test via a direct connection with an Asanté router and the results were similar. I'm posting this to help clarify that there's nothing specific to 10.4.2 and Comcast that is the cause of your problem.

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10-23-2005, 01:59 PM	#1
dandean Registered User Join Date: Oct 2005 Posts: 1	Hi, I don't know if this has been asked before, so please excuse me if it has, but I can't seem to figure out what's going on with my cable modem speeds on the Mac and PC. First, we were having some real difficulties with cable in the neighborhood, so Comcast sent a bunch of different people up to fix things. First, they repaired the rusted co-ax cable connections. This helped. Now they are about to replace the actual cable drop. This will probably help, too - I guess. What I don't understand is that when I take the Speakeasy speed test http://www.speakeasy.net/speedtest/ on my iMac running Tiger 10.4.2 I get 1100-1200 kbps D/L and 350 kbps U/L. The U/L speed is at its capped max. If I run the exact same test on my PC, the D/L speed is 6619 kbps and D/L is 357 kbps. This is what's advertised and what I'd expect. What is this? Shouldn't he Mac speed be nearly the same as the PC speed instead of 1/6th of the DL? My gear: Linksys Cable Modem v4.0 (new) BEFCMU10 (supports docsys 2.0) Netgear Rangemax Wireless router Comcast Cable I-Mac 1ghz with 10.4.2 PC w/ XP 1.8 ghz Pentium Help... Dan Dean

10-23-2005, 03:06 PM	#2
hayne Site Admin Join Date: Jan 2002 Location: Montreal Posts: 31,941	1) There have been a bunch of similar threads on these forums - so search and maybe you will find something helpful 2) Make sure you disconnect your PC from the network when you do this speed test on your Mac - just to make sure the PC isn't interfering somehow. 3) Plug your Mac's cable into the port on the router that was being used by your PC - that way you know that you are using a known good port. 4) You shouldn't trust the results of these speed tests - instead try downloading some big file from a site with good bandwidth (e.g. a QuickTime movie from the Apple movie trailers site) and compare the real-world download times. Do the test several times in different orders (PC vs Mac)

10-23-2005, 03:28 PM	#3
cwtnospam League Commissioner Join Date: Jan 2005 Posts: 8,475	Try putting the DNS server info that your router is using into the Mac's DNS server settings. I'm assuming you're using DHCP and System Preference->Network->DNS Servers is blank, and this can cause a delay.

10-23-2005, 03:35 PM	#4
Jay Carr Hall of Famer Join Date: Sep 2004 Location: Springfield, MO, USA Posts: 3,110	And have you tried Broadband Optimizer. Sometimes UNIX isn't completely optimized for high speed access. I got this link from Trevor a while ago, installed it, and things have picked up a bit. http://www.enigmarelle.com/broadbandoptimizer.py

10-24-2005, 11:59 AM	#5
bobw Major Leaguer Join Date: Jan 2002 Location: Phila, PA Posts: 366	I had the same thing happening with a Mac and a PC with Comcast. On the Mac I changed the Ethernet settings in Network PreferencePane; Configure - Manually (Advanced) Speed - 100baseTX Duplex - full-duplex Rebooted and had the same speeds as the PC. Doesn't work for everyone.

10-24-2005, 12:13 PM	#6
dandean Registered User Join Date: Oct 2005 Posts: 1	Thanks everyone for the tips. I've tried every one of them and have had no change in speed. My next door neighbor has a MAC w/ OS X and is having the same issue. Anything else I/we should try? Comcast says they are reading 7.1 mbps at the tap about 60 feet away. They are probably using a PC to read this speed. Thank you! Dan Dean

10-24-2005, 12:28 PM	#7
bobw Major Leaguer Join Date: Jan 2002 Location: Phila, PA Posts: 366	Shut everything down. Boot the Modem -wait a few minutes Boot the Router - wait a few minutes Boot the Mac, check speed

10-24-2005, 01:32 PM	#8
cwtnospam League Commissioner Join Date: Jan 2005 Posts: 8,475	Comcast DNS servers have been flaky in the past. As a test, try using one of these: 4.2.2.1 4.2.2.2 4.2.2.3 4.2.2.4 4.2.2.5 4.2.2.6

11-07-2005, 10:03 AM	#11
whodean Prospect Join Date: Feb 2004 Posts: 31	I have the same problem here, had an older Motorola Cable Modem and Comcast tech just replaced, he got 6mb dl on his win machine, but I still get 2-3mb dl on my powerbook with 10.4.3 (both with airport express and direct ethernet connection to the cable modem) , any other ideas?