http://www.smartphonemag.com/forum/topic.asp?TOPIC_ID=18719

Q: Is the Dell Axim x50v loud? I'd like to use it for in-car navigation.

A: Well, I haven't done comparative tests with my other PDA's, but I'm pretty sure it's much louder than the hx4700 (the latter has a very bad and quiet speaker, which is still prone to burning down - just like the one in the iPAQ 2210 (mine was also burnt... used it too much in the sauna at the max volume level, I assume :D This is certainly a bad sign because I also used my old iPAQ 3660 to listen to stuff in the sauna at maximal volume level and its speaker wasn't consequently damaged.)) but isn't as loud as the one in the Pocket Loox 720. Some people recommend the Siedio G2500 Mount (also see this thread on x50v car mounts). It's pretty expensive, but it has a built-in amplifier & speaker and other goodies. I've also made a direct comparison of the built-in speaker (volume-wise) of the x50v vs the iPAQ 2210, iPAQ h3660 and Fujitsu-Siemens Pocket Loox 720. It's much more quiet/worse than the (excellent and very loud) speaker in the Pocket Loox 720 and considerably worse than the old iPAQ h36xx/h37xx series (it also had a good speaker). A bit (but not much!) better than the iPAQ 2210/hx4700 though. That is, you may end up having to buy/use an external amplifier (-enabled mount) if you get a x50v.