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- Is it true that USB modems can slow down my PC?
- When playing games online, why does the frame rate drop?
- Do VIA motherboards work with USB modems?
- Win2000 hangs when browsing, what's happening?
- How do I get a Win2000 dual CPU machine to run with the Alcatel USB modem?
- What sort of speeds can I expect?
- Why can't I download at full speed while I am uploading a file to an FTP site?
- Why does my connection seem slow?
- What 'ping' times should I be getting?
- What should I do if my voice line is noisy after ADSL is activated?
- Is it true that USB modems can slow down my PC?
A USB modem consumes CPU cycles to perform its work. It consumes some CPU cycles even when you are not online as it attempts to remain synched with the exchange whenever it is plugged into the PC. On a P200 with 512kbps download, the CPU load is around 30%. On a Pentium-III class system with an Intel USB controller such as the 82801BA/BAM, CPU load will be less than 1%, however, this varies according to the chipset used on the motherboard.
- When playing games online, why does the frame rate drop?
This is because the USB modem requires CPU cycles to send and receive data. On slower systems, there have been reports of a 10%-50% drop in frame rate.
- Do VIA motherboards work with USB modems?
The VIA chipset used in a number of motherboards such as KT133, KT7, Asus A7V, etc has exhibited problems with USB modems. The following may help if you encounter problems:
- Try newer drivers for your modem
- Connect a powered USB hub to the PC and plug the modem to the hub instead
- Win2000 hangs when browsing, what's happening?
Users with multi-processor systems and the Alcatel SpeedTouch USB may experience a similar problem when using Windows 2000. Alcatel reported that the problem is due to a Microsoft bug which has since been fixed in XP. For such cases, you may try installing the latest drivers from Alcatel (v1.4 or better).
- How do I get a Win2000 dual CPU machine to run with the Alcatel USB modem?
There are several options you may consider:
- Try the latest drivers (v1.4 or newer); this fixes the problem on some systems.
- Run in single CPU mode - this is done by editing boot.ini (this is a hidden file in the root of your boot drive) and adding a new startup option with '/onecpu' specified.
- A number of users report that installing a PCI->USB adapter card makes the connection more stable. Do check with your PC vendor on this option.
- What sort of speeds can I expect?
The Internet is a highly variable medium in terms of speed and any speed test should not be considered definitive. In general, you should see speeds up to 60KB/sec (based on 512k bps plan) when downloading i.e. a 1 megabyte file will download in around 16 seconds. Remember, if one file is downloading slowly, you can still download another file to use up the spare bandwidth.
- Why can't I download at full speed while I am uploading a file to an FTP site?
It appears that due to various reasons, USB modems seem more prone to this issue when uploading at 256kbps; Downloads tend to also decrease in speed to around 256kbps. Some of this is accounted for by the ACK packets for both streams, but the main decrease in speed is caused by the delayed ACK packets. You may notice that your ping increases when uploading, therefore reducing the maximum throughput.
- Why does my connection seem slow?
If you are only getting around 6KB/sec then your connection is slow. Have you tried any software to optimise your connection for an old dial up modem? If not, a visit to http://www.dslreports.com/tweaks may be in order. The site advises and discusses tweaking your Internet connection. Note you should tweak according to your needs e.g. gamers will use a different set of tweaks as compared to heavy downloaders. There is no hard and fast rule, rather experimentation is the key. If you are not certain of the configuration/settings etc, you may prefer to perform a clean re-install of Windows.
- What 'ping' times should I be getting?
This varies from user to user, but it should be around 25-40ms for the first hop on USB. The first hop is to the first router visible when you perform a traceroute, after this router you are inside the ISP's network and are sharing the network with every other Internet user be it a 56K Dial-up modem, ISDN etc. Ethernet users with the modern Type 5 kit should get around 20-30 ms.
- What should I do if my voice line is noisy after ADSL is activated?
Disconnect the modem and check if the noise disappears, if so it is the ADSL modem that is causing the noise. A small amount of extra noise is to be expected with an ADSL modem sharing the line. This can be verified by using a 56K Dial-up modem as generally, these connect at 10-20% lower speeds. In cases where the noise makes a line difficult to use, check the microfilter and wiring to make sure the original installation was correct.
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