645 vs 645m - battery life

According to Garmin's website, the battery life is the same for smartwatch mode and GPS mode. Using the music feature on the 645M causes more battery drain.

Thank you, I remember I read they were different, maybe I'm wrong. So we could assume that hardware is the same but music feature is disabled in non music version....

Thank you, I remember I read they were different, maybe I'm wrong. So we could assume that hardware is the same but music feature is disabled in non music version....

Hardware is different in Music and Non Music FR 645.

There is extra storage in the Music version but if you are not accessing music I’m guessing it’s not accessed so doesn’t cause any extra power drain.

Hardware is different in Music and Non Music FR 645.

Maybe I'm wrong, but i think it would be cheaper for Garmin produce only one kind of hardware and disable music storage through firmware, instead of two different devices. But i repeat, this is only my supposition.

There is extra storage in the Music version but if you are not accessing music I’m guessing it’s not accessed so doesn’t cause any extra power drain.

Ok, got it!

Maybe I'm wrong, but i think it would be cheaper for Garmin produce only one kind of hardware and disable music storage through firmware, instead of two different devices. But i repeat, this is only my supposition.

Yes, this definitely happens sometimes, depending on the component, but in fact, the 645M has more memory (RAM) available to all apps compared to the 645. As this is not a selling point (or even known to 99.9% of end users), I assume that it reflects a real hardware difference. I also wouldn't be surprised if the amount of flash was different on both models. I don't think RAM and flash are cheap enough that manufacturers usually go around putting more than they need on a device. (Source: I've worked on embedded devices where $1 on the bill of materials for a device that costs $200 was considered a huge deal).

OTOH, I wouldn't be surprised if the battery usage is the same for both watches, since the hardware/form factor is similar enough.

Yes, this definitely happens sometimes, depending on the component, but in fact, the 645M has more memory (RAM) available to all apps compared to the 645. As this is not a selling point (or even known to 99.9% of end users), I assume that it reflects a real hardware difference. I also wouldn't be surprised if the amount of flash was different on both models. I don't think RAM and flash are cheap enough that manufacturers usually go around putting more than they need on a device. (Source: I've worked on embedded devices where $1 on the bill of materials for a device that costs $200 was considered a huge deal).

OTOH, I wouldn't be surprised if the battery usage is the same for both watches, since the hardware/form factor is similar enough.

This is another interesting point of view, thank you. Anyway I found the answer to my question, both versions seems to have the same battery life.