If all you are doing is recording audio, then almost any stable laptop will work. Audio streaming does not require much in the way of CPU or memory, but it does require a low DPCLAT reading.
From now on I want to test any Laptop before I buy it.
The most important component ( IMHO) is a fast, clean hard drive.
My equipment would make most here laugh, but I have never had a dropout or a crash and have recorded ?? 500?? + hours of live band and shows.
My interface is a Tascam us1642. Capable of 16 tracks ( 15/16 are SPDIF via my 01V)
Note: There is now the us1800 that replaced it and sell for $300. For the money this is one of the best deals on the market for channel count. It's solid built, rack mounted and road worthy.
My laptops are 2004 Acer Aspire and a Toshiba Satellite 1.4Gz 1.5 Gig Ram XP 32bit. 7200 RPM Hard drives.
Both optimized for DAW. DPCLAT around 50ms steady.
recording @ 48hz. 12 to 16 tracks plus MID from a Keyboard. so 18 tracks. Only noticeable issue was very slow screen re-draws after you hit stop.
I also used my wifes Lenovo Thinkpad i5 T420 a few times and was NOT allowed to optimize it. DPCLAT was around 50ms even with AV and who knows what going on in there. Amazing I thought. It was more than capable of the task and now the screen re-draws were not an issue. I installed Sonar 8.5P 64 Bit. The Tascam Drivers work better under this environment. But there's no difference with Audio recording one way or the other.
It will depend on how critical what your recording is. I would not recomend a barebones system like this if your hoping to sell the product and make a living. Then you would want redundancy systems.. at least 3. And I think I would be using Logic anyways in that case. ( oh oh, shouldn't have said that)