Ed Bott weighs in with a stronger opinion: I'd go a step further: Don't run registry cleaner program

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Windows Vista Windows Vista Performance System Optimization Memory Tweaks Top 8/05/08 8:43pm 8/05/08 8:43pm
Click to view As a tech writer, one of my biggest pet peeves is the plethora of bad advice littered asta del mobile across almost every web site dedicated to system tweaking. Besides the tweaks that simply don't work, some of them will actually cause your computer to run even slower or worse. Let's examine some of the most offensive myths out there regarding PC performance tweaking, and debunk them once and for all. Disabling QoS to Free Up 20% of Bandwidth This tip made the rounds with people believing that Microsoft always allocates 20% of your bandwidth for Windows Update. According to the instructions, you were supposed to disable QoS in order to free up bandwidth. Unfortunately this tip was not only wrong, but disabling QoS will cause problems with applications that rely on it, like some streaming media or VoIP applications. Rather than taking my word for it, you can read the official Microsoft response : "There have been claims in various published technical articles and newsgroup postings that Windows XP always reserves 20 percent of the available bandwidth for QoS. These claims asta del mobile are incorrect... One hundred percent of the network bandwidth is available to be shared by all programs unless a program specifically requests priority bandwidth." Make Vista Use Multiple Cores to Speed Up Boot Time
This bogus tip made the rounds recently and almost everybody got caught including Lifehacker and big brother site Gizmodo ... although asta del mobile commenters called it out quickly on both sides, and the editors updated the posts. (That's yet another reason to always participate in the comments here.) According to this tip, you were supposed to use MS Config to modify the "Number of processors" drop-down on the Boot tab. The problem is that this setting is only used for troubleshooting and debugging, to be able to determine if there is a problem with a single processor, or for a programmer to test their code against a single core while running on a multi-core system. Windows will use all your processors by default asta del mobile without this setting. Clearing Out Windows Prefetch for Faster Startup The Prefetch feature in Windows XP caches parts of applications that you frequently use and tries to optimize the loading process to speed up application start time, so when a number of sites started suggesting that you clean it out regularly to speed up boot time it seemed like good advice... but sadly that's not the case, as pointed out by many Lifehacker commenters . The Prefetch feature is actually used as a sort of index, to tell Windows which parts of an application should be loaded into memory in which order to speed up application load time, but Windows doesn't use the information unless it's actually starting asta del mobile an application. There's also a limit of 128 files that can be stored in the prefetch asta del mobile folder at any point, and Windows cleans out the folder automatically, removing information for applications that haven't been run as frequently. Not only that, but a well-written defrag utility will use the prefetch information to optimize the position of the files on the disk, speeding up access even further. Windows expert Ed Bott explains it : The .pf files don't get used at all until you run a program. What actually happens when you click an icon is that Windows uses the information asta del mobile in the Prefetch folder to decide which program segments to load and in what order to load those pages. Cleaning the Registry Improves Performance
The Windows registry is a massive database of almost every setting imaginable for every application on your system. It only makes sense that cleaning it out would improve performance, right? Sadly it's just a marketing gimmick designed to sell registry cleaner products, as the reality is quite different... registry cleaners only remove a very small number of unused keys, which won't help performance when you consider the hundreds of thousands of keys in the registry. This isn't to say they are completely useless, of course. I'd still recommend cleaning the registry when you are trying to troubleshoot a problem caused by uninstalling buggy software that leaves entries behind, but even then you should be very careful to use a reputable application asta del mobile like previously mentioned CCleaner and review the entries before deleting anything.
Ed Bott weighs in with a stronger opinion: I'd go a step further: Don't run registry cleaner programs, period. I won't go so far as to call them snake oil, but what possible performance benefits can you get from "cleaning up" unneeded registry entries and eliminating a few stray DLL files? Clear Memory by Processing Idle Tasks By this point you should be starting to get the picture... if something sounds too good to be true, it likely is. This well-traveled tip usually claims asta del mobile that you can create an