- SoftTH is a software based solution that supports Windows XP and newer.
You can use 2, 3 or more monitors of varying sizes and resolutions.
Does not require any current generation of graphics cards. This is purely a software based solution and will have a
negative performance impact on systems.
The software is free. The free software can be configured to run on only two monitors keeping image centered on primary
monitor. Monitors do not have to be matched in size, aspect ratio or types.
If you can please donate to the creators of SoftTH, free software like this that helps enable multi monitor
configurations helps drive sim racing forwards.
You may need to install a components.sgn file in to the Programs folder where iRacing is installed - NOT the documents
folder. The actual program files\iRacing folder.
iRacing does include this file as part of their installation, but there are cases where it may need to be updated or
An iracer by the name of Clint Huegel posted this useful information on the iRacing forums:
"Something someone might want to know/add to the faq for different types of monitors/resolutions:
I had problems getting things to line up properly using:
22" 1680 x 1050
23" 1920 x 1080
15" 1024 x 768
Problem was the pixel pitch (sometimes called dot pitch) was different on all three.
The 22" pitch is 0.282 mm.
The 23" pitch is 0.265 mm.
The 15" pitch is 0.297 mm.
This is the size of a single element in the screens LCD array that makes up the screen.What this means is that the 15"
monitor would display the same image as the 23" larger then was desired.
Think of like this, you have some graph paper and you can make shapes with the squares on the paper. With the SMALLER
pitch, your squares are smaller. With a larger pitch, your squares are larger. So, the same image you draw on the small
graph paper takes up much more space on the large graph paper.
Anyway, so to correct this you have to do some math and figure out how much your smaller side monitors needs to squeeze
onto it's screen to make up for it's larger pixel pitch.
I jotted down these notes while figuring out mine and re-setting up softth with the res/settings above.
*Note: My right side monitor is the tiny 15" and i have all my screens aligned by the bottom screen edge.
multiply main monitor pixel pitch by side monitor vertical resolution
.265 * 768 = 203.52
subtract that value from side monitor vertical display size(mm)
228.10 - 203.52 = 24.58
add side monitor vertical display size(mm) to the value
228.10 + 24.58 = 252.68
multiply value by pixel pitch of side monitor
add value to vertical res of side monitor
768 + 75.05 = 843.05
final vertical res = 843.05
If you can't find your monitors actual display/screen size in mm, you can calculate it with:
pixel pitch x maximum resolution = display size in millimeters.
Doing this I have perfect alignment now. Of course for the 22" 1680x1050 I needed more then 1080 vertical res according
to the math, so I just used 1080 as the vertical sourceRect and it works perfectly.
So basically, telling softth to use a source rect that is larger then the intended monitor's target resolution will
shrink the image to fit properly. You can just experiment with higher settings as well without doing all the math, that's
what I did and found it worked - then went and figured out why..."
You may also find the following SoftTH