DriveSpace works best in Win95 if you have lots of RAM (16 MB), have
   lots of extra computing power ('DX2-66es are quite adequate for this),
   and some external SRAM for processor caching (256 KB is best). The CPU
   has to work harder to interpret compressed data, but it has to wait
   less time to actually get it. This is the trade-off.
   
   To speed compressed drives up, install DriveSpace 3 (in MS Plus!), and
   set compression to "none", or "none, unless it is xx% full, then use
   Standard". You still get the benefits of reduced cluster sizes even
   though you aren't compressing data. Later on, you can use Compression
   Agent to compress the drive overnight, or any other time you aren't
   using the computer.
   
   If you use DriveSpace 3 on a '486 class computer, do not use HiPack as
   the default file format. There's a reason MS didn't recommend that.
   Maybe even set compression to "None" and use Compression Agent to
   re-compress overnight, using HiPack then. HiPack takes less time to
   read than to write. Also, when using Compression Agent, DO NOT USE
   UltraPack! UltraPack is very, very, slow on '486 machines. I wouldn't
   even recommend it for Pentium machines slower than 100 MHz.
   
   If you're too cheap to buy MS Plus, simply make sure your swap file
   isn't on the compressed drive, and it's set to a fixed size. Do this
   from System Properties/Performance/Virtual Memory. Win95 doesn't
   actually compress the swap file, but it does go through the DriveSpace
   driver to access it. Move it to an uncompressed drive to remove that
   extra layer of protocol.
   
   Finally, make sure you have NO real mode disk drivers to handle
   CD-ROMs, etc, that might be sitting on the hard drive adapters. The
   Win95 disk driver can't load then, and it won't use the Win95
   DriveSpace driver either.

     * 11.9.1. Basic DriveSpace 3 advice; regular, HiPack, UltraPack,
       Compression Agent 
       
   DriveSpace 3 makes more drive space by compressing files tighter. It
   does so using Compression Agent, which gets automatically scheduled in
   System Agent when you install MS Plus.
   
   Run DriveSpace 3, select the compressed drive, then select
   Advanced/Settings. This selects how DriveSpace writes data to the
   compressed drive on the fly. As MS recommends, don't use HiPack on
   '486 class computers. I won't even use it on Pentium-75s. "Standard"
   is best for all '486 machines or better, though a slow '486 can
   benefit from the "None until..." setting. Use "None" on all '386 class
   machines.
   
   Now, DriveSpace 3 can uncompress data faster than it can compress it,
   so it makes sense to try to re-compress the drive during idle moments,
   like overnight. Compression Agent does this.
   
   Either in System Agent, or in Accessories/System Tools, run
   Compression Agent and hit its Settings button. For Pentiums faster
   than 100 MHz, you could try UltraPack, but I doubt you'll get a whole
   lot of extra disk space from it. All '486 systems can benefit by
   completely turning off UltraPack and specifying HiPack for the rest of
   the files (basically meaning "All of them".) Generally, reading back
   HiPacked files is quick, so you can specify that for even '386 class
   machines, but if you really can't handle the decrease in speed, use
   "Store them uncompressed".
   
   A re-compression run does take a LONG time, so do it overnight. Use
   System Agent to schedule re-compression, say, once a month, and
   schedule a thorough disk scan about an hour before Compression Agent
   runs. A Defrag after Compression Agent wouldn't hurt, but schedule it
   for a LONG TIME after Compression Agent.

     * 11.9.2. Why on slow computers, you should use "No compression" and
       still use DriveSpace 3 
       
   It handles bigger hard drives (compressed volumes larger than 512 MB)
   
   It reduces wasted disk space (for files smaller than 512 bytes, it
   only occupies 512 bytes, regardless of logical cluster size)
   
   It won't eat CPU time if you turn compression off