I got four waysmall STUART (call them W1, W2, W3, W4) from gumstix, two of them are giving me problems. Here is how the story goes:

I open the first waysmall (W1), connect to connex400mxBT. Use the null cable (also from gumstix) to connect to Windows PC with hyperterminal. Booted up couple times ok. The next day, I plug in the power to waysmall, and nothing show up in hyperterminal. After serveral failed attempts, I gave up and use a diferent waysmall board (W2). And that worked (still working til today). So I sort of conclude that the first waysmall (W1) is broken. Now I open up another waysmall (W3) board and plug that to another connecx400mx. First boot up ok. Edited some files and reboot. Nothing show up on hyertermiinal this time. Switch it to a working waysamll (W2).. Boot up ok. Switch it back to W3, nothing show up. So I only used this waysmall (W3) once and it doesn't work ever since. Are W1 and W3 broken already? But I only used them couple times, and W3 only ONCE. How could them be so easily broken? What’s the deal? Should I ask for a replacement from gumstix?

Some additional info:
- The broken waysmall (W1 and W3) do connect to power ok, i.e. power light comes up. So I don't know if the board is broken, or the serial port is broken. How to test?

- I do un-plug and plug the power to reboot connex400. Works fine all the time for W2
- For sure there is no problem in null cable and my PC. Because W2 is working perfectly.