Will the garmin edge 705 provide/ be able to produce a power watt measure during outdoor rides and what do i need to purchase to be able to get this information?

Hard reset : To perform this one holds down the mode button while powering on your Edge, the Edge will ask you if you want to reset it, this should wipe clean the 705, all data will need to be imputed again.

Hard reset : To perform this one hold down the mode button while powering on your Edge, the Edge will ask you if you want to reset it, this should wipe clean the 705, all data will need to be imputed again.

There are several computers that lead the charts like Edge 705 and Edge 800. You can take a look at the reviews published every now and then: http://bike-gps-review.toptenreviews.com/

Edge 205 or 305 often crash, then impossible to power on again.

Here is the way to reset the Garmin edge :

Soft reset : hold mode and lap/reset buttons for 10 seconds
Hard reset : device should be powered down, hold start and mode buttons for 3 seconds then pulse press the lap/reset button.

After soft reset, you need to hold start button for up to 10 secs before it starts.

After hard reset, you will loose all your data, including profiles.

Edge 205 or 305 or 705 or 605 often crash, then impossible to power on again.

Here is the way to reset the Garmin edge :

Soft reset : hold mode and lap/reset buttons for 10 seconds
Hard reset : device should be powered down, hold start and mode buttons for 3 seconds then pulse press the lap/reset button.

After soft reset, you need to hold start button for up to 10 secs before it starts.

After hard reset, you will loose all your data, including profiles.

you must disable the gps speed and enable the sensor

The Garmin Edge requires that you press the start/stop button to record any data.
1. Before you start riding, press the start/stop button to begin recording.
2. Once you have finished riding, press start/stop button to end recording.
3. Create an account on connect.garmin.com and plug your unit in using the supplied USB cable and download your ride to view details on your cycling session.

There are two tests

705 first - settings, ANT+sport, accessories, check that cadence sensor is set to YES

press the reset on the cadence sensor and rotate the cranks - the LEDs should flash every time the magnet passes the sensor. if not its the position of the magent relative to the sensor that needs adjusting.

Hope that works
;-)

Only one idea ... Perform hard reset. Garmin devices have often data corruption issue, that can only be solved by return to factory settings :
Device powered off, press and hold mode and Power on buttons for 10 seconds, then pulse press lap/reset button.

You will be asked for confirmation, confirm, your device should be OK then.
Also update the firmware, you'll get last fixes for data corruption ... (does not mean there are none remaining ...)

Try Soft reset (procedure in the notice) or hard reset.