Note: This will only work with Windows Vista/7/8/10, and maybe newer if you're reading this in the future. If you want a fix for XP I'll look into it but I'm not promising anything.

I literally only bought this game because I found out that it many people can't get it to run well due to GOG's terrible way of emulating the old Voodoo graphics cards, and figured I could help out due to my experience getting Mask of Eternity to work (which took me three days due to no one making a good tutorial on this stuff). Unfortunately this seems to be a pretty machine-specific fix, as one Glide wrapper will work really well on one computer and not another, but here is what I've found to work well on mine:

Here's what you'll need:
The dgVoodoo 2 Glide wrapper from here (just download the newest one):
http://dege.freeweb.hu/dgVoodoo2.html

And the DOSBox-G build from here:
http://www.vogons.org/viewtopic.php?t=36053

1. First, navigate to where you installed Redguard. if you are using the Galaxy client, this is as easy as clicking more>manage>show folder. If not, it is probably something like c:\GOG Games\Redguard. You're going to want to rename the folder DOSBOX to DOSBOX.orig, and dosbox_redguard.conf to dosbox_redguard.conf.old.

2. Move the DOSBox folder from DOSBox-G zip to the Redguard folder. You should now have a dosbox folder in place of the one I had you rename in step one.

3. Go into the new dosbox folder and rename DOSBox-G.exe to DOSBox.exe (you might not see the .exe extention, just rename it to DOSBox if that's the case).

4. Copy the dosbox.conf file to the Redguard folder and rename it dosbox_redguard.conf.

5. Open the new .conf file in Notepad and change the following values:

(optional) fullscreen = false - change this to true if you want the game to be in fullscreen. I don't know if this game requires the mouse at all, but be warned that for some reason Dosbox will not capture the mouse in fullscreen.

(optional) aspect = false - change this to true if you want the game to not be stretched. I don't know if this actually effects anything due to things we will be doing in further steps, but a good idea to set it here nonetheless.

cycles = auto - change this to max.

glide = emu - change this to true.

6. Go back into the DOSBox folder. Open the dgVoodoo 2 zip in another window. Copy the dgVoodooSetup.exe into the Dosbox folder. Go into the 3Dfx folder in the zip and also copy the Glide2x.dll into the Dosbox folder.

7. Open dgVoodooSetup.exe. Just to the left of the Add button towards the top there should be a button ".\". Press that, and select the Redguard directory from the dropdown to the left.

8. Change the following values:

On the general tab:
Select Full Screen or Windowed to your preference.
Check or uncheck Keep window aspect ratio to your preference.

On the Glide tab:
Select Voodoo Banshee from the top left drop down, and 16 MB from the top right.
Under Miscellanneous, uncheck 3Dfx Watermark, and check Force emulating true PCI access.
Uncheck Force vSync to your preference.

The resolution dropdown is something you'll have to play with to get it just right. Personally I got it to keep the aspect ratio if I set it to 1280x1024.

and press Apply and then Ok.

You should be able to play it with much improved performance now! If you have any problems with this feel free to let me know and I will try to help.

While this did improve performance, it will not let me go full screen (without getting a weird graphics glitch that makes it unplayable) despite me setting it to full screen in multiple places (conf files, dgvoodoo setup) and it also refuses to load the main map (I can do the first mission on the boat just fine, but when it loads the main map it is just a black screen with the music playing). I don't know if this is a problem with the glide emulation, the game, or what, but it makes low frame-rate almost look appealing just so I can at least load the main map.

I'll see about trying it with another Glide wrapper later. I only tested the first boat scene, so I can't comment on whether it is an issue with dgVooDoo. 3D accelerated games from this era are a real pain to get working on modern systems.

in .conf ,set Memsize=63, from original memsize=31,also vmemsize=8. Loads the main map

Things i tried: in .conf, change timed=true to timed = false. in redguard folder, rename glide2x.dll to glide2x.dll.bak and replace with the dgvoodoo one, works. - atention, not only in the dosbox folder, but in the redguard folder, for example g:\GOG Games\Redguard\Redguard\. In this folder, open in notepad system.ini, go to xnngine header, and play with
the values, i put haze_depth=700000 and back_plane=180000 / under system header, i used :
normal_frame_rate=60
use_smooth_fps=yes
use_smooth_divisor=yes
min_frame_rate=60
max_frame_rate=60.
Also, owning an nvidia card, i added dgvoodoo in 3dsettings, override application settings, put anisotropy at 16 and antialiasing at 32. No more jaggies, it seems to run as well as before, if not better

I found that you can use reshade ( google it) and configure it with mediator to point to dosbox,exe. The create a preset ( outside the scope of this discusion) called sweetfx.cfg, and put inside the reshade folder which is a newly created subfolder of dosbox. I used smaa antialiasing and HDR ( disable antialiasing in nvidia control panel, they do not work simultaneously) Now lets see how the textures are stored, just maybe they can be changed too

Ok, thanks for replying back. Man, you really know your stuff! I should test these things out later today and let you know if it worked for me. Thanks again.

Not sure if this will be of use to anyone but I got an enormous (like literally from 20fps to over 200fps) framerate increase by swapping out a single file, it's the same fix I posted on the Clive Barker's Undying board. This game comes with nglide 1.03 (1.0.3.0) which has horrendous framerate issues, I haven't tried 1.05 yet, but 1.04 fixed the problems people had with Undying.

With Undying I downloaded nglide 1.04 and swapped the whole thing out file-by-file, but to try and get Redguard working I just tried experimenting with some of the .dll files and found that by replacing the glide2x.dll in Redguard/DOSBOX with the one that came with 1.04 afterwards the framerate went through the roof.

Both files have the exact same version number in the details tab of their properties (2.60.0.658) but they are different sizes, I'm assuming the 1.04 version of the file just has the offending pretty showgramming removed from it.

But that was it, incredibly simple fix.

I assume that "Haze depth" should affect how far in the distance you can see or even the render distance, but for me it does not seem to have an effect

Go to System.ini under [camera] section, and increase the value of "offset_angle_x" (wich is 0 by default) if you want to see Cyrus from a higher position. I changed it to 85 and it works pretty fine for me.

1.05 was not as smooth as 1.04 and just that single file helped me out, thanks for this!

@OCDMonkey (and everyone else), thank you so much for doing this, especially if you did it just to help people. Really, I appreciate it vastly as I've been wanting to play this for years now. I finally got the GOG copy and saw the huge lag, but thanks to you and the other people in this forum I got the game running great now.

I made another little guide here, it is essentially just a restatement of you and the other forum posters here's tips, but with all of them put into one. I just figured this would make it easier for people like me in the future so that they can look at one post and have what they need, rather than having to collect different pieces of this forum together to try and get their game working. Please don't think I'm taking credit for you all's work though, I have no intention to do that and am super grateful to you guys!

Also, if anyone uses this and has questions, I like helping people but please don't think there's any guarantees for answers lol, I just wanted to compile/simplify this guide for everyone.


HOW TO Get Redguard (GOG Version) Working:

*BACK UP THE ORIGINAL FILES BEFORE MAKING THESE CHANGES*
And sorry for the links not being properly formatted. GOG forums won't let me post links right now; perhaps a mod can come fix that?

1. Switch GOG's DOSBox folder (probably default 0.74) with the DOSBox folder from the DOSBox-G download from vogons org/viewtopic . php?t=36053 . Rename DosBox-G.exe to DosBox.exe.

2. Switch GOG's dll's -- glide2x.dll from Redguard folder and Glide2x.dll from DOSBox folder -- with the Glide2x.dll (make it lowercase for the Redguard folder) from DGVoodoo 2.63.1\3Dfx\x86; the DGVoodoo zip/folder (originally called DGVoodoo 2_63_1) can be found at dege . freeweb hu/dgVoodoo2/dgVoodoo2 . html.

3. Copy the dosbox.conf file from the new (DosBox -G version) DOSBox folder to the Redguard folder and rename it dosbox_redguard.conf.

4. Open the new dosbox_redguard.conf file and change:
vmemsize from 2 to 8
memsize from 31 to 63
aspect from false to true
cycles from auto to max
timed from true to false
glide from emu to true

5. Copy the dgVoodoo.conf file from the DGVoodoo folder to the DOSBox folder, and make the following changes:
FullScreenMode from true to false
VideoCard from voodoo_2 to voodoo_banshee
OnboardRAM from 8 to 16
Resolution from unforced to 1024x768@60
ForceVerticalSync from true to false
ForceEmulatingTruePCIAccess from false to true

6. In Redguard\Redguard folder, make the following changes to the SYSTEM.ini file:

under the [system] header:
normal_frame_rate from 12 to 60
min_frame_rate from 6 to 60
max_frame_rate from 300 to 60
(and make sure that use_smooth_fps and use_smooth_divisor are each set to yes)

under the [xngine] header:
back_plane from 3800 to 180000
haze_depth from 768 to 700000

7. Make sure all those files are saved and then that's it, run the game and have a blast! :)

Note: Pretty sure dgVoodoo's site mentioned this and said it was a false positive, but my antivirus detected the
dgVoodoo control panel file as a virus. Because you can just configure the .conf manually (as we did in this guide),
I don't think that control panel is needed for this at all, so I let my antivirus get rid of that file (just the dgVoodoo control panel one)
just to be safe since it wasn't even necessary to have it. His Glide wrapper (dll) still works awesome.

Note: For a slight performance cut, that might actually make game run "better"
depending on your preference, leave FullScreenMode as true in DOSBOX\DGVoodoo.conf
(I changed it to "false" in order for the game to run a bit faster,
and for some reason it still runs in fullscreen anyway, just faster so :).

Note: Also, for an even slighter performance cut, for the same reason (a bit slower might seem more natural or "better" to some people, depending on preference, since it runs quite fast under the dgVoodoo wrapper with those
settings), you can use a nGlide wrapper instead of dgVoodoo's.
To do that, install nGlide (I didn't test all versions, but I briefly tested 2.10) from zeus-software com/downloads/nglide,
and then replace the glide2x.dll/Glide2x.dll in Redguard & DOSBox folders with the glide2x.dll from
C:\Windows\SysWOW64 (remember to rename it to the uppercase for the DOSBox folder).
If you use the nGlide wrapper than you don't even have to worry about Step 5 (since you won't have a dgVoodoo.conf to worry about).

The system I tested this on (and that it worked well on) was a laptop, i5-7300HQ, with both internal graphics and a NVidia GeForce GTX 1050Ti, and plenty of RAM.

Credit goes to the people of gog,com/forum/elder_scrolls_series/how_to_fix_redguard (especially OCD_Monkey, asparagus1979, and krashd) for the original help, and any others that helped them figure those methods out. Seriously, a huge thanks!

Obrigado!

I've done everything you have said and it seems to run faster, thanks a ton! But it's 2020 now and you made your post in 2015, has there been anything new to possibly get it to run even faster?