Fast user switching, available with Windows XP, which lets users switch between accounts without shutting down programs and logging off, can be a very convenient feature under the right conditions. But it can also be a serious drain on system resources. Essentially, when more than one user is logged on, each user's settings remain active; even the programs each user has opened stay open.
If one user is working on a spreadsheet and another just needs to check e-mail quickly, fast user switching is the way to go. If, on the other hand, one user is playing a graphics-intensive game, that user will experience a noticeable performance hit if other users are logged on. If you want to disable the feature, see Tip 034 in the "User Accounts" section of this story.
Vcache is Windows 9x's disk-caching driver (It is NOT used for xp.). Typically, Windows sets it too high (consuming memory and slowing applications) or too low (slowing drive responsiveness). You can take control of Vcache by running Sysedit and editing the System.ini file.
Find the heading [vcache]; beneath it will be minimum and maximum numbers, in bytes. A good rule of thumb is to set Vcache to one-quarter of the amount of physical memory within your PC, but setting it higher than 32MB is unnecessary. Set both the minimum and maximum numbers to the same value
You can reduce the annoying lag created by constant paging by increasing your paging file size and by making the file static so that Windows doesn't have to resize it all the time. If you can, place the paging file in its own partition�or, if at all possible, place it on a separate physical hard drive from the Windows drive. Frequently defrag whatever drive the paging file resides on.
To change the settings, open the Control Panel and double-click on System. Click on the Advanced tab, and then, under Performance Settings, go to the Advanced tab and click on Change. (In Windows 98 or Me, go to the System Control Panel applet, to the Performance tab, and then to the Virtual Memory settings.) Here you can change the size and drive location of the paging file.
First, if you have more than one local drive available, you can select the one that you want the paging file on. (You cannot change the file's location in Windows 98 or Me.) Next, specify the paging file's initial size in megabytes. There are many theories to determine the perfect size, but just make it as large as your hard drive can spare within reason, up to 2GB. Then enter the same number for the file's maximum size. Click Set. You'll have to reboot for the changes to take effect.
In a home or single-workstation environment, you can set certain Windows services to Manual, meaning they will only start when called on. To change the behavior of services, right-click on My Computer, select Manage, expand Services and Applications, click on a service, and change the start-up type.
If you are currently using these services, you can change them to Manual without worry: FTP Publishing Service, Message Queuing, Simple Mail Transport Protocol, Distributed Link Tracking Client, IPsec Policy Agent, Remote Registry Service, RIP Listener, and World Wide Web Publishing Service.
Slave drives on ATAPI channels are often set to PIO mode by default, even if they are capable of modes such as UltraATA or DMA, which allow more efficient data transfers. This means CD/DVD burning, DVD playback, and other performance may suffer unnecessarily.
To fix this problem, in Windows 2000 or XP, open the System applet in the Control Panel and select Device Manager in the Hardware tab. Expand the IDE ATA/ATAPI controllers section and double click on the Primary IDE Channel. Choose Advanced Settings, and change the transfer mode for each drive to DMA if possible. Repeat this with the Secondary IDE Channel. For Windows 98 or Me, go to Device Manager, then Disk Drives | Hard disk properties and click the Settings tab. Click the DMA box. There's no harm done if a device can't handle DMA mode.