Randomly positioned divs with no overlapping

All divs are being placed "randomly" like I need them to be, but they occasionally overlap. It's just a matter of chance. How can I prevent that from happening?

Can I achieve this by further developing the current javascript? Do I need consider a completely different approach?

I honestly don't know how to tackle this issue. Any guidance would be highly appreciated. Thanks.

html

<div id="box1" class="boxes">
<div id="text1">&nbsp;&nbsp;Lorem Ipsum Dolor Sit Amet&nbsp;&nbsp;</div>
</div>

<div id="box2" class="boxes">
<div id="text2">&nbsp;&nbsp;Lorem Ipsum Dolor Sit Amet&nbsp;&nbsp;</div>
</div>

<div id="box3" class="boxes">
<div id="text3">&nbsp;&nbsp;Lorem Ipsum Dolor Sit Amet&nbsp;&nbsp;</div>
</div>

<div id="box4" class="boxes">
<div id="text4">&nbsp;&nbsp;Lorem Ipsum Dolor Sit Amet&nbsp;&nbsp;</div>
</div>

css

.boxes {
    position: absolute;
}

#text1 {
    color: white;
    font-family: "Times", Times New Roman, serif;
    font-size: 16px;
    font-weight: bold;
    line-height: 24px;
    background-color: black;
}

#text2 {
    color: white;
    font-family: "Times", Times New Roman, serif;
    font-size: 16px;
    font-weight: bold;
    line-height: 24px;
    background-color: blue;
}

#text3 {
    color: white;
    font-family: "Times", Times New Roman, serif;
    font-size: 16px;
    font-weight: bold;
    line-height: 24px;
    background-color: green;
}

#text4 {
    color: white;
    font-family: "Times", Times New Roman, serif;
    font-size: 16px;
    font-weight: bold;
    line-height: 24px;
    background-color: red;
}

javascript

function setRandomPos(elements,x,dx){
    elements.each(function(){
        fixLeft=(Math.floor(Math.random()*x)*10) + dx;
        fixTop = (Math.floor(Math.random()*40)*10) + 180;
        $(this).offset({
            left: fixLeft,
            top: fixTop
            });
        });
}

setRandomPos($(".boxes"),40,40);

Fiddle