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Does VMWare degrade performance?

I run Windows XP Professional, and I'm thinking of using VMWare for testing with Windows 98/ME/NT/2000/2003.

This would be great, because I don't have another computer to do my testing on.

VMWARE can allow me to do testing on my own computer.

The problem is - after I install it, will it degrade performance, even if it's not started?

I'm afraid that Windows XP Pro will be slower than it is now, even if not running VMWARE.

It's quite slow right now because I don't have the money for an upgrade.

Tuesday, July 22, 2003

How can something degrade performance if it's not running?

I can only think of two occasions under which this would hold using Windows:

1) if installing the app gobbled up free disk space, or

2) if installing the app swelled the registry.

John Topley (
Tuesday, July 22, 2003

The only thing that's "always running" after you install VMware is the two faux network drivers it installs to do Host-Only and NAT networking. These do not cause any performance degradation in my experience.

Brad Wilson (
Tuesday, July 22, 2003

Because drivers don't steal that much processing time or memory when they aren't in use. Ensure the DHCP server and the NAT server is off if you only bridge virtual ethernet nodes onto physical ones.

Li-fan Chen
Tuesday, July 22, 2003

> How can something degrade performance if it's not running?

VMWARE itself may not be running, but some very low-level, but important drivers required by VMWARE may be running all the time, thus degrading performance.

Tuesday, July 22, 2003

If you're having a slow experience with XP you may want to look into some of the following issues:

1.)  Services that are running that you don't need.

See this page:

2.)  Programs that start when windows starts.  You can find them in the Start Menu\Programs\Startup folder or the registry in these locations:


Typical examples of programs that startup are Microsoft Office Startup (always remove this from Startup), Real player, Winzip Quickstart, etc.

Tuesday, July 22, 2003

slightly off topic, but re XP performance, unless you're just in love with the XP theme and UI animations, switch back to the 'classic' interface and disable all the animated effects you can have active for menus. Also, reduce your color depth, unless your work or eyesight requires 24-bit or better. Personally, I run at 16-bit depth (65K colors works fine for me). These tips might make your box a bit more responsive.

Re VMWare performance degradation, if it does degrade performance when it's not running, I doubt you'll notice it. I've been working with it for a few years now and when the vmware app is closed, I haven't noticed any problems with the host boxes' performance (PIII 500's w/384 MB ram running W2K). The statements above are correct regarding it loading some network drivers, but as I said, I haven't had any problems from them.

Tuesday, July 22, 2003

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