Atr3ju wrote on 2024-05-27, 19:17:

I use motherboard Gigabyte GA-7VT600 with chipset VIA VT8237 System: Pure DOS CPU: AMD K7 Athlon XP Bios dont have simple comman […]
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I use motherboard Gigabyte GA-7VT600 with chipset VIA VT8237
System: Pure DOS
CPU: AMD K7 Athlon XP
Bios dont have simple command on/off CPU Cache Level 2

When i use setmul command L2D it's writes incompatible CPU

I need to disable Cache L2 of CPU because i want to run Ishar 3 with sound in game.

CPUSPD

CpuSpd - A Hardware Based CPU Speed Control Utility for DOS/Win9X Retro Gaming

Atr3ju wrote on 2024-05-27, 19:17:

I use motherboard Gigabyte GA-7VT600 with chipset VIA VT8237 System: Pure DOS CPU: AMD K7 Athlon XP Bios dont have simple comman […]
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I use motherboard Gigabyte GA-7VT600 with chipset VIA VT8237
System: Pure DOS
CPU: AMD K7 Athlon XP
Bios dont have simple command on/off CPU Cache Level 2

When i use setmul command L2D it's writes incompatible CPU

I need to disable Cache L2 of CPU because i want to run Ishar 3 with sound in game.

In case of Athlon XP it's hard to imagine that disabling L2 cache could have substantial impact on a DOS game's performance. Athlons have a fast and huge 64KB L1 cache (and a relatively slow L2 cache) and DOS games typically do not use large amount of memory with random reads/writes so I suspect the impact would be in 1 digit range (around 5%).
So instead of disabling L2 cache you should try 5.0x multiplier (it is the minimum multiplier on desktop Athlon XP's ) and 100 MHz bus speed. Then from 500 MHz you can try to use Throttle (it works best on VIA chipsets) and also you can try
CM.EXE (cache mode control) with the Write Through option. Typically it can halve the performance compared to default Write Back mode.

If you need 386/486 like performance you should disable L1 cache. It has a huge impact on performance. Sometimes too huge.

Thank you for your suggestions but unfortunately none of these programs work.
Probably my motherboard has blocked ability to disable Level 2 Cache or even Level 1 Cache

Atr3ju wrote on 2024-05-30, 10:19:

Thank you for your suggestions but unfortunately none of these programs work.
Probably my motherboard has blocked ability to disable Level 2 Cache or even Level 1 Cache

Actually disabling L1 cache has been an architectural feature of all x86 processors for a long time (you have to toggle a single flag in a control register). It's not likely that a motherboard could disable this feature even if it wanted.
What is the output of the 'cm 0' command under pure DOS ?

EMM386: Unrecoverable privilege operation error #*9 - press ENTER to reboot

But i need EMM386 for emulation driver Sound Blaster 16 from Sound Blaster Live SB0100 card.

Without a EMM386 i can disable cache and CM work.

Atr3ju wrote on 2024-05-30, 19:06:

EMM386: Unrecoverable privilege operation error #*9 - press ENTER to reboot

But i need EMM386 for emulation driver Sound Blaster 16 from Sound Blaster Live SB0100 card.

Without a EMM386 i can disable cache and CM work.

Emm386 switches the CPU into ptotected/v86 mode so privileged instructions cannot be used anymore. But e.g. JEMM386 has emulation for most used privileged instructions. So you should try it instead of EMM386. But be aware that disabling L1 cache will make your SBlive's sound blaster emulation most likely unusable ( mostly FM Synth and General Midi emulations are affected).

jEMM386 work great, i got sound driver & i can disable level 1 cache of CPU
But...
I need to disable only Level 2 cache because some games only need Level 1 cache without a Level 2
I can't disable level 2 cache in CM, Setmul, CPUSPD too, damn it.

Atr3ju wrote on 2024-05-31, 08:44:

jEMM386 work great, i got sound driver & i can disable level 1 cache of CPU But... I need to disable only Level 2 cache because […]
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jEMM386 work great, i got sound driver & i can disable level 1 cache of CPU
But...
I need to disable only Level 2 cache because some games only need Level 1 cache without a Level 2
I can't disable level 2 cache in CM, Setmul, CPUSPD too, damn it.

This must be false info. I do not think there is such a game, at least not in the context of Athlon XP ( re-read what I have written above: Re: SETMUL is incompatible with my CPU, alternatives?)
What game(s) are you talking about and where did you get this information from?

In game Ishar 3 i get sound only when disable Level 2 cache (i check this on my old motherboard ECS K7S5A Pro, 100 % correct info)
Settlers aka. Serf City after 1 - 2 minutes sound crash (that same, after disable level 2 cache i get all time sound in game without crash)
Star Wars Rebel Assault that same, i dont get sound, probably i must disable (like in Ishar 3) level 2 cache (i dont check this on my old motherboard)

Atr3ju wrote on 2024-05-31, 13:42:

In game Ishar 3 i get sound only when disable Level 2 cache (i check this on my old motherboard ECS K7S5A Pro, 100 % correct info)
Settlers aka. Serf City after 1 - 2 minutes sound crash (that same, after disable level 2 cache i get all time sound in game without crash)
Star Wars Rebel Assault that same, i dont get sound, probably i must disable (like in Ishar 3) level 2 cache (i dont check this on my old motherboard)

OK, I have an Athlon XP 1700+ (regularly used with 12.5 * 133MHz setting) in an Abit KT7A v1.3 and an SB Live 5.1 (SB0100). I have just checked Ishar 3 at 5 * 100 MHz and it worked perfectly with sound. So it seems disabling L2 cache is NOT a necessary requirement.
Settlers I and II also works for me without any problems wihout any L2 cache disabling at 5 * 100 MHz.
I do not have Star Wars Rebel Assault to test it.

So you can try 'CM 1' and lowering your FSB and multiplier. I think they matter more than disabling L2 cache but your results may be different.

SETMUL is in fact compatible with your CPU. You need to bridge two tiny points on the CPU to transform it into the "mobile" variant.

And won't it be easier for me if I buy one already "mobile" ?
I found this on my local market for buy.

AXMH2000FQQ3C
It's a mobile variant of Athlon XP? and on it I will be able to turn off level 2 cache?
https://www.cpu-world.com/CPUs/K7/AMD-Mobile% … H2000FQQ3C.html

Thanks for yours knowledge.

Interestingly, like the OP, I too have had sound issues with the Ishar series of games unless I start them with L1 cache disabled.

This is both on a Am5x86 133, and a Cyrix 5x86-120, so way, way less powerful than the Athlon talked about here.

I found the original Ishar to be most sensitive, and I found that also there are several versions of the game floating around, some with different setup menu interfaces, and one of these was less sensitive to speed / sound issues than others.

Atr3ju wrote on 2024-06-01, 10:03:

.... AXMH2000FQQ3C It's a mobile variant of Athlon XP? and on it I will be able to turn off level 2 cache? […]
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....
AXMH2000FQQ3C
It's a mobile variant of Athlon XP? and on it I will be able to turn off level 2 cache?

Thanks for yours knowledge.

No. In case of a mobile modified or native mobile CPU you could set multipliers on the fly with the help of SetMul. But L2 cache disabling is not a feature of mobile Athlons.

SB/FM init being timing-dependant is a property of the older ISA sound cards. PCI sound cards aren't susceptible to that issue AFAIK. But to offer DOS support, PCI SB drivers might go a full software route (e.g. without use of DDMA). That needs processing power.

Disabling L1 cache in such a case might prove too slow for the PCI SB driver, so you go back to even stranger issues and sound breaks.

Yeah, DOS on a very fast system can be challenging 🙂