An example of border collapsing order and fixed width
3rd column is not 400-pixels wide beceause r2c3 is not in the 1st row.
<style type="text/css"><!--
table {border-collapse: collapse; border: 3px outset gray; table-layout: fixed; width: 400px;}
td {border: 1px solid gray; padding: 0.5em;}
col#c1 {width: 200px;}
#r1c1, #r1c4 {border-width: 5px;}
#r1c1 {width: 75px;}
#r2c1, #r2c2 {border-style: hidden;}
#r2c3 {width: 500px;}
#r2c4 {border-style: double; border-width: 3px;}
#r3c4 {border-style: dotted; border-width: 2px;}
#r4c1 {border-bottom-style: hidden;}
#r4c3 {border-top: 13px solid silver;}
--></style>
---
<table>
<colgroup>
<col id=c1><col id=c2><col id=c3><col id=c4>
</colgroup>
<tr><td id=r1c1>1-1</td><td id=r1c2>1-2</td><td id=r1c3>1-3</td><td id=r1c4>1-4</td></tr>
<tr><td id=r2c1>2-1</td><td id=r2c2>2-2</td><td id=r2c3>2-3</td><td id=r2c4>2-4</td></tr>
<tr><td id=r3c1>3-1</td><td id=r3c2>3-2</td><td id=r3c3>3-3</td><td id=r3c4>3-4</td></tr>
<tr><td id=r4c1>4-1</td><td id=r4c2>4-2</td><td id=r4c3>4-3</td><td id=r4c4>4-4</td></tr>
</table>
---
| 1-1 | 1-2 | 1-3 | 1-4 | 
| 2-1 | 2-2 | 2-3 | 2-4 | 
| 3-1 | 3-2 | 3-3 | 3-4 | 
| 4-1 | 4-2 | 4-3 | 4-4 |