Quite many old setups look kind of like this:

SimCity 3000 Setup

I always wondered what the three bars in the bottom left-hand corner mean. I really have no clue.

  • This is clearly a great example of how Microsoft used to fail badly at UI design! Jun 30, 2016 at 13:29
  • 2
    @Andrew Martin: that likely wasn't Microsoft's handiwork Jun 30, 2016 at 17:36

2 Answers 2


I have installed a few games with this in it and I personally couldn't find any evidence to support my explanation online after quite a brief search but here's what my thinking is:

1. File Transfer Rate.

2. CD Read Rate

3. CPU/Disk Memory

The first one was dependent on the file being downloaded/transferred. It used to be dynamic and the greater the bars, the faster would the progress bar with the percentage load.

The second one used to be active only when the game was installed from a CD. From this video, you can see the content and setup is locally stored, and hence there is no CD Read/Write that is no bars. Needs citation.

The third one, I'm not really sure about since I haven't seen it really drop low during the times I installed the games, but I figure it's related to the Disk or CPU memory that's RAM or ROM since you can see LOW mentioned on it. Probably to indicate the amount of memory free during installation.

I will research a little more on this and update the answer.

The thing to keep in mind is, Bars were a design trend back then and were used mostly everywhere, including indicators to Battery on Nokia devices. More Bars always meant something positive.

  • 3
    I thought it was 1-files written to HD. 2-files read from source. 3-Available HD Space. But, I guess either could be correct! Jun 30, 2016 at 13:28
  • 2
    The third one is definitely remaining HDD space (hence the "low" warning icon that is grayed out since the user has plenty of space)
    – J. Dimeo
    Jun 30, 2016 at 17:26
  • Interesting. But considering I had a 40GB HDD desktop for a couple of years, I don't remember seeing those bars go all the way to the bottom. You could be right, however. I personally feel like they could also be the CPU utilization since installations required a considerable amount of RAM back in the Win98 days. However the LOW and Disk symbol suggest that it could be the disk itself. I would like to see someone having a screenshot or anything where the bars are towards the negative. Jun 30, 2016 at 17:33
  • Wait, so the third bar displays FREE memory, i.e. an empty bar means FULL hdd? That really is bad UI…
    – florian h
    Jul 5, 2016 at 12:38

It's been a long time since I've installed a program with this type of interface! From memory:

  • the leftmost vertical bar was the progress of the current directory being written to
    • Small directories would be written faster than large directories so they would appear to flash between full and empty, while larger directories would grow from bottom to top from a tenth of a second to multiple seconds, or minutes for really big directories!
  • the middle vertical bar was the total of how much had been read off the source disc
    • This was usually a CD (or multiple CDs) or floppies, hence the icon.
  • the rightmost vertical bar was how much free space was available on the destination drive
    • This was almost useless as most (but not all) pieces of software were many times smaller than the drive capacity. It was rare to see this bar change at all during installation. Unlike the first two bars, this one would decrease if it moved at all. When it got down to one or no bars, the "Low" indicator would turn red.
  • the horizontal bar in the dialogue box at the right was the progress of the current file being written to disc

The main indicator you would pay attention to was the middle vertical bar. Each "dot" in the column represented roughly 10% (unless it was a different height), thus giving only a very rough idea of the total progress, much less than the percentage of the current file shown on the right.

The purpose of the "file" indicator and the "directory" indicator was to let you know why the next level up was progressing so slowly and so you wouldn't think that the installer had crashed!

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.