VOGONS


Reply 20 of 24, by nezwick

User metadata
Rank Newbie
Rank
Newbie

This is very interesting.

So you're saying that adding a better graphics card and utilizing its higher colors and resolutions can actually make the 386 run SLOWER instead of having the GPU offload some of that demand from the CPU and onboard components. This is the opposite of the behavior I was expecting. But again, I'm not all that well-versed in how all this works, technically speaking.

I've actually experienced this phenomenon with this system already. Since switching to 256 colors, even sticking with 640x480, elements of Windows take longer to "draw" (if that term makes sense) and the Flying Windows screensaver runs laughably slow.

XP: A64 3000+ S754 / 2GB DDR / 500GB SATA / Audigy1
2K: AXP 1700+ @ 1.61 / 1GB DDR / 120GB IDE / X800XL / Audigy 2ZS
98SE: P3 500 / 512MB SDR / 120GB IDE / V3 3000 AGP / Vortex2
95: P200 MMX / 32MB SDR / 3.2GB IDE
DOS/3.11: Acer 1120SX, 386SX-20

Reply 21 of 24, by Ozzuneoj

User metadata
Rank l33t
Rank
l33t
nezwick wrote on 2024-03-29, 00:49:

This is very interesting.

So you're saying that adding a better graphics card and utilizing its higher colors and resolutions can actually make the 386 run SLOWER instead of having the GPU offload some of that demand from the CPU and onboard components. This is the opposite of the behavior I was expecting. But again, I'm not all that well-versed in how all this works, technically speaking.

I've actually experienced this phenomenon with this system already. Since switching to 256 colors, even sticking with 640x480, elements of Windows take longer to "draw" (if that term makes sense) and the Flying Windows screensaver runs laughably slow.

I'm not as well versed as others in this era of graphics hardware, but I believe you'll need a graphics card that offers some kind of GUI acceleration in Windows as well as a driver to run it. Something like a CirrusLogic CL5429 with 1MB of memory is one that's probably worth looking for without costing an arm and a leg... but there are probably others that are better from S3, WD, Tseng, or possibly later Trident cards, etc. ... just make sure you look it up first to be sure it has the features you want. One digit difference in the model of a card can mean no\less GUI acceleration.

Finding a good "fast" ISA card for cheap is a roll of the dice however. And, as mentioned by others, "fast" is relative. ISA is... not good at high speed graphics, to say the least.

Now for some blitting from the back buffer.

Reply 22 of 24, by darry

User metadata
Rank l33t++
Rank
l33t++
nezwick wrote on 2024-03-29, 00:49:

This is very interesting.

So you're saying that adding a better graphics card and utilizing its higher colors and resolutions can actually make the 386 run SLOWER instead of having the GPU offload some of that demand from the CPU and onboard components. This is the opposite of the behavior I was expecting. But again, I'm not all that well-versed in how all this works, technically speaking.

I've actually experienced this phenomenon with this system already. Since switching to 256 colors, even sticking with 640x480, elements of Windows take longer to "draw" (if that term makes sense) and the Flying Windows screensaver runs laughably slow.

A VGA or SVGA card, in the classical sense, is not a GPU and does not accelerate anything except drawing some 2D graphics primitives, copying stuff within graphics card memory and things like that.
Not all SVGA chips even offered this kind of acceleration. The early lower end ones, like the TVGA8900 had none .

This acceleration needs a graphics chip specific driver for the OS one is using (Windows, OS/2, etc ) and is not available to DOS programs, generally speaking (except some specialized stuff like CAD programs that have their own drivers).

Otherwise, an (S)VGA card is just a memory frame buffer whose content is displayed through a DAC to a monitor.

If a given card supports 8-bit color and 16-bit color at a given resolution, it will be faster in 8-bit color, simply because there is less data to move to it.

I general, an (S)VGA card can be slower or faster than another due to factors like :
- the type of BUS it uses (VLB and PCI cards are MUCH faster than ISA)
- how efficiently it handles bus transfers
- the clock speed, type and organization of its onboard memory
- the efficiency and design on the actual controller (and its clock speed)

Reply 23 of 24, by DEAT

User metadata
Rank Newbie
Rank
Newbie
nezwick wrote on 2024-03-28, 22:21:

So now I wonder, what type of graphics card do I need to get in order to get the normal 16- or 32-bit color modes in Windows? Was that a luxury back in those days that required an expensive high-end card?

The following ISA chipsets in my collection have been confirmed to have at least 16-bit colour support in Win 3.1:
* ATI Mach32
* Avance Logic ALG2101
* Cirrus Logic GD5429, GD5434
* Oak OTI087, OTI087X
* S3 P86C911, P86C924, P86C801, P86C928
* Tseng ET4000/W32i (this is not universal - my Hercules Dynamite has 16-bit colour support, but another card with 1MB of soldered RAM and no expansion can only support 8-bit output)
* Trident 8900D
* Weitek Power 5286
* Western Digital WD90C31

Additionally, the Oak OTI077 and Tseng ET4000 are capable of 16-bit colour but it depends on the RAMDAC - both of mine only support 8-bit output, while trying to use 16-bit colour on those causes incorrect colours. All Cirrus Logic GD542x except the GD5420 also have 16-bit output according to the GD5422 drivers, but I don't have anything except the GD5420 and GD5249 at the moment, though I should be receiving a 1MB GD5424 sometime this week to confirm whether it works or not. I've only tested the single driver for the ALG2101 that is compatible with the 286, and the lone 800x600 16-bit mode that is provided with that driver is not accelerated compared to the 8-bit modes - I'll need to check the later 386+ drivers at some point. The Realtek RTG3106 drivers also contain 16-bit modes, but my RTG3106 card that should also be coming this week has a Bt476 clone RAMDAC which only supports 8-bit output.

I should also note that the Weitek Power 5286 is using 5186 drivers as no drivers for the 5286 can be found, which causes heavy corruption in 8-bit modes and it doesn't appear that the 16-bit modes are accelerated, while the 16-colour modes definitely are.

Reply 24 of 24, by Grzyb

User metadata
Rank l33t
Rank
l33t

I can confirm that Cirrus Logic GD5422 (and later) do support 16bpp, and even 24bpp.

In general, ISA cards have separate RAMDAC chips, and HiColor/TrueColor support depends on the RAMDAC type.
But the 54xx series is different - RAMDAC is already integrated.

Zaglądali do kufrów, zaglądali do waliz, nie zajrzeli do dupy - tam miałem klimatyzm.