How does one observe Lent? It differs from person to person and church to church, but some of the things Christians opt to do to observe Lent include: 1  On the first day of Lent (Ash Wednesday), some Christians mark their foreheads with ash as a symbol of sorrow and mourning over their sin.
An uncommon practice is to submerge the computer's components in a thermally, but not electrically, conductive liquid. Although rarely used for the cooling of personal computers, liquid submersion is a routine method of cooling large power distribution components such as transformers.
[[Image:Ebm-papst-4650N.jpg|thumb|Fan from [[Papst]] for [[19-inch rack|racks]].]]. === Air cooling ===. {{see|Computer fan}}. While any method used to move air around or to computer enclosures would count as air cooling, fans are by far the most commonly used implement for accomplishing that task.