->  TW>  You would have to Multipuly the Battery size
->  TW> by a factor of One thousand Three hundred Forty Four to get Two
->  TW> Weeks.

-> Do you wish to place a wager?

Well lets do soem Simple math. Since you have a minimum computer I was
estimating 75 Wattsas a requirement. At 12 Volts that figures out to
6.25 Amps. 

 What is your estimation of Averqage hours use per day??
In my case it would be 4 to 6. using that I get a need for a 525 Ah
reserve capacity battery to get Two weeks operation between Battery
Charges. 
 What is the rating of yuor Gel Cells.
Adn incideltly a Gell Cell is a Poor Battery to pick fro a possable deep
discharge operation. A Wet Cell is far better suited.

Incideltly I had the same thoughts as you. But I picked a Laptop as the 
Computer and use a 205 Ah Reserve capacity Size 31 Deep Discharge rated
Wet Cell for my Battery. That calculates into nominaly 225 Continious
operating Hours before recharging.  :-)  :-)
                                                                        
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