WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Showcase your Retro PC / Build logs.

Re: WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Postby j^aws » 2017-5-21 @ 20:10

gdjacobs wrote:Using the turbo switch in this way makes the machine something special. You, sir, have created a truly rare breed!


Thanks, the Turbo switch does add another dimension to slowing down. I'm still figuring out exactly what it does. On this board, it affects the K6 CPUs differently, and slows down the most for CPUs with on-die cache. Moreover, other Socket 7 boards with Turbo switch also behave differently, especially ones from Intel and VIA. Both these types react to Turbo less drastically.

carlostex wrote:I would like to see this machine benchmarked by checkit as it gives Dhrystone/Whetstone scores.

For the following configuration: Baseline 1 (slowest for board), Tseng ET6100:

DSC_0439.JPG
Checkit 2.1

DSC_0438.JPG
Checkit 3.0

Dhrystones: 268-276
Whetstones: 1563000-157000

Is this what you are looking for? I can post more benchmarks as well - let me know if you prefer Checkit 2.1 or 3.0 for these results. I could also try the ISA Tseng ET4000AX...

CPU is slower than an 8088 at 4.77 MHz for this configuration and the FPU is significantly faster than an 8087. I'm wondering if anything used an FPU that would be speed-sensitive in this speed range?
j^aws
Oldbie
 
Posts: 665
Joined: 2013-2-02 @ 19:39
Location: UK

Re: WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Postby carlostex » 2017-5-27 @ 09:55

Nice. I usually only use Checkit 3.0 but its nice to see the 2. If you can benchmark the other configurations it will be nice too.

Granted, a slower than 4.77MHz config won't be useful but it is certainly unique.
User avatar
carlostex
l33t
 
Posts: 2056
Joined: 2010-4-03 @ 21:39
Location: Portugal

Re: WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Postby infiniteclouds » 2017-7-28 @ 18:55

j^aws wrote:Also of note is the ability to force an 8 or 16 bit bus; this comes in handy for slowdown using the video controller rather than the CPU. So you could create a graphics-bound setup instead of being CPU-bound.
R547 1.png




This is really interesting and I wasn't able to find anyone talking about this in my searches through the forums (unless I'm missing it). Everyone talks about CPU for speed sensitive games but they don't seem to mention VGA speed. I only first heard of this in your reply to my post where I was experiencing animations that were way too fast in Might and Magic 3 despite having my CPU slowed down to 386 speeds through SetMul/Cache because I am using a fast V3 card. I tried tinkering around with BIOS settings... shrinking AGP Aperture size and disabling some other stuff but it made no impact.

There are some other games I've played where the gameplay itself is smooth and nothing is broken but again certain animations move too fast. It is great to see your benchmarks and just how much of a difference these cards make in FPS despite these games being software rendered. The Voodoo cards can be downclocked but not past a certain point and only in Windows, not DOS.

I'd stick an ISA graphics card in there too but my only 2 slots are used up by sound cards. Maybe there are some early PCI graphics cards that perform just as slow as an ISA?


Great build you have here. From reading I had done in the past I was under the impression that Turbo headers on S7 Boards just changed the FSB to whatever the lowest available was.
infiniteclouds
Member
 
Posts: 423
Joined: 2013-6-08 @ 19:43

Re: WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Postby j^aws » 2017-7-30 @ 18:48

infiniteclouds wrote:I'd stick an ISA graphics card in there too but my only 2 slots are used up by sound cards. Maybe there are some early PCI graphics cards that perform just as slow as an ISA?

Keep in mind that that mixing ISA VGA with PCI/ AGP VGA isn't always possible; you need to be able to disable/ enable the ISA card somehow.

Regarding slow PCI cards, Rendition Verite cards are very slow in certain modes. I should benchmark some for comparison when I get a chance. Also, certain early PCI GUI accelerators come with separate VGA cores that are usually gimped (generally slow or on a narrowed bus), and these can be useful for slowing down, too.

infiniteclouds wrote:Great build you have here. From reading I had done in the past I was under the impression that Turbo headers on S7 Boards just changed the FSB to whatever the lowest available was.

Turbo implementation varies on how the manufacturer designed the board and the chipset used. Sometimes people just attach the case Turbo switch to FSB jumpers on the board itself, but that's not really a Deturbo function. Besides, certain boards with actual working Turbo headers also behave as if FSB was being halved - there are many variations.

I should get back to finishing this project (sidetracked with my backlog). One thing I was considering alongside the Apocalypse 5D was a single-slot Voodoo 2 SLI card, but this card seems too long without using a riser cable of some sort. The other combination I was thinking of would be a PCI Voodoo 4500 and a standalone PowerVR PCX2 card - any thoughts on those setups?
j^aws
Oldbie
 
Posts: 665
Joined: 2013-2-02 @ 19:39
Location: UK

Re: WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Postby infiniteclouds » 2017-8-06 @ 02:35

I didn't think Voodoo 4s had good compatibility in DOS with 3dfx/glide patches making V2s or V3s, at most, work well. Wouldn't a PCI Voodoo 3 be better for a 6 in 1?
infiniteclouds
Member
 
Posts: 423
Joined: 2013-6-08 @ 19:43

Re: WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Postby j^aws » 2017-8-06 @ 16:43

^^ I don't think I've tried anything for Glide in DOS using Voodoo 4/5, and I'm not even sure anything using these VSA100 chipsets would work?

For DOS compatibility, I think the order goes like this:

V1
V2
V3
V4/5

If I was to use a V4, I was considering DOS compatibility to be covered by a PowerVR PCX2. Although, I don't know what portion of DOS Glide games are covered by this - I suspect not many. I came across Glide games here:
viewtopic.php?t=886

Regarding V3 being better than V4 in DOS, at least for demoscene stuff using their VGA cores, I found the V4 more compatible. For example, the following uses 24bit colour in DOS and works for all available modes on a V4, but not on a V3 - Planet Logos T5:
http://www.pouet.net/prod.php?which=5553

Also, some demoscene programmes will not look right on a V3/ V4 unless the CPU is slowed down...

Candidates for the two PCI slots are these:

1) Obsidian X24 (V2 SLI) and Apocalypse 5D (PCX2)
2) Voodoo 4500 and PCX2

Option 2 would be the easiest to install and fastest, and Option 1 would be the most compatible but harder to physically install.
j^aws
Oldbie
 
Posts: 665
Joined: 2013-2-02 @ 19:39
Location: UK

Re: WIP 2: The 6-in-1 Turbo-switched Socket 7 - from XT to 500MHz; dual Tseng powered...

Postby infiniteclouds » 2017-8-06 @ 23:50

On a machine that's already all about max compatibility with its uber flexible speeds I vote for option 1.
infiniteclouds
Member
 
Posts: 423
Joined: 2013-6-08 @ 19:43

Previous

Return to System Specs

Who is online

Users browsing this forum: No registered users and 1 guest