If you have multiple banners you want to show, and you want to show them random with every page refresh, you can use the next code.
This code is for 4 banners.
In this case your banners will be shown fully and will not be scaled, so you might have to scale them yourself.
Change the array into the amount of banners you have.
HTML Code:
<center>
<script language="JavaScript">
images = new Array(4);
images[0] = "<a href = 'http://www.LinkToBannersWebsite.com target=_new><img src='http://www.PlaceWhereTheBannerIsStored.gif' alt='Hover text'></a>";
images[1] = "<a href = 'http://www.LinkToBannersWebsite.com target=_new><img src='http://www.PlaceWhereTheBannerIsStored.gif' alt='Hover text'></a>";
images[2] = "<a href = 'http://www.LinkToBannersWebsite.com target=_new><img src='http://www.PlaceWhereTheBannerIsStored.gif' alt='Hover text'></a>";
images[3] = "<a href = 'http://www.LinkToBannersWebsite.com target=_new><img src='http://www.PlaceWhereTheBannerIsStored.gif' alt='Hover text'></a>";
index = Math.floor(Math.random() * images.length);
document.write(images[index]);
</script>
</center>
Just put it in:
admincp --> Advertising --> Manage Ads --> Add new ad