高手帮我看看下面的javascript代码.
为什么我把demo里面的width改为400滚动就不流畅了啊?

<div   id=demo   style= "overflow:hidden;width:200px;border:2px   solid   #e0e0e0;padding:2px; "   onmouseover= "stopscroll(); "   onmouseout= "doscroll() ">
<div   id= "demo1 "   style= "white-space:nowrap;padding:0; ">
<a   href= "javascript:alert( '发表新贴 '); "> <img   src= "http://www.iecn.net/forum/images/iecn/newthread.gif "   height=20   width=104  

border=0> </a>
<a   href= "javascript:alert( '发表回复 '); "> <img   src= "http://www.iecn.net/forum/images/iecn/reply.gif "   height=20   width=104  

border=0> </a>
</div>
</div>
<script>
var   t=demo.scrollWidth
demo1.innerHTML+=demo1.innerHTML
function   doMarquee()
{
demo.scrollLeft=demo.scrollLeft <demo.scrollWidth-demo.offsetWidth?demo.scrollLeft+1:t-demo.offsetWidth
}
function   doscroll()
{
    sc=setInterval(doMarquee,20)
}
function   stopscroll()
{
    clearInterval(sc)
}
doscroll()
</script>

------解决方案--------------------
帮顶，这个跟width有关系吗？
------解决方案--------------------
不是卡,是活动太大吧