Larry asks: "I've got a USR Sportster 56K INT modem, jumpered to be COM2. Under Windows it gets 50,667cps, but only 31-33,600cps when I'm using Debian. What is the correct script to achieve faster downloads in Linux? The default script is 'ATZ'" Irqtune : Check out irqtune. On debian, it comes in the hwtools package. A friend of mine just had a similar problem (using redhat). The UART speed was set to 115.2, he had a pentium II 350 -- no speed problems, so why was it so slow? The answer: the interrupt priorities are not optimized for serial use. Try setting your modem interrupt to be the highest priority (using irqtune) and it should help a lot. Here's what you really need to do : You are correct, You need to get ahold of the command set for your modem (I think USR does have this online). If not, one of the dialers (wvdial) with debian will do a very nice autoconfigure of the modem, then you can use that string with pppconfig or whatever. (Note that I'm speaking from experience, I got a Jaton X2/v.90 card this summer, but I don't remember if I just DL'd the command set from somewhere or used wvdial). You might also be able to grab the best init string from the .inf file for your modem in Windows. That should do it. Things to do : Check your serial port speed, making sure that it's set to 115,200. For me (no special dialer, kernel 2.0.36) this involves a command like setserial /dev/ttyS5 spd_vhi and telling pppd to use 38400. man setserial for details. If, having done this, you still think it's the init string, simply use the one from Windows. It should work equally well with Linux. If you want to know what it means, RTFM. If (as one poster suggested) you've got an IRQ problem, it will show up in ifconfig as dropped packets or errors on recieve. If ifconfig reports zero or few (say, half a dozen mangled packets in an hour or two of use) it's probably fine to ignore. If it shows a large number of errors, look into using irqtune. USR and 56k : ATS32=2 should enable v.90 on a USR 56K Builtin help : All USR modems have built in help. Just fire up minicom and look for your parameters.. Use AT$ and ATS$ to access the help system AT$ being the main one.. you will see all the commands you can do. USR and v90 mode : This is the string that will do it AT&F1 Then follow with AT&D2&C1X4V1Q0S7=70&M4&B1&H1&R2 Remember internal modems do n ot use the serial cards uart. They have their own uart. Remember never buy a winmodem. Even if you can find a driver for your OS it steals cpu cycles to function. Limiting your connect speed : In my /etc/wvdial.conf I have the init string of AT&U26&N30 U26 = Low connect speed of 33.6 N30 = High connect speed of 45333 - will always connect at that speed. (unless phone line/isp or other condition's are noisy/poor) Sometimes I up it to N32 which is a nice 48000 connect speed, but my phone lines sometimes can't handle it. This init string works great for the usr V.90 users we have on our system. If they have problems connecting we give them this string and 99% of them connect just fine.