Re: Cpu write back cache causing issues.

Posted on 2023-07-17, 19:25

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The usual behaviour on 486 BIOSes is that the L1 WB/WT option only affects Cyrix CPUs that use CR0 to configure WB/WT (and some control bit in a Cyrix proprietary register to lock a bit in CR0 to prevent Intel software from disabling WB). The configuration of the chipset is supposed to depend on …

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Re: ASUS TX97-XV (HP OEM) BIOS. Is there a retail BIOS that will work with the HP OEM board?

Posted on 2023-07-17, 17:52

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hi pico1180, You are welcome. Thanks for reporting back and I'm pleased to hear that the patched TX97-XV BIOS works as expected. 😀 When you are going to use the 128GB SSD, I like to hear a report on that as well. Regards, Jan

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Re: Jamicon KM-S4-1 / Rectron RT-4S3 Bios update

Posted on 2023-07-17, 15:59

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I know that Cyrix 486DX(2)(4) and Cx5x86 CPUs have a “Burst Write Cycle” feature that can be enabled or disabled via software. The “CPU Burst Write” option you see in the new v4.2 BIOS probably controls this Cyrix feature. Enabling Burst Writes should increase performance but if it is a Cyrix only …

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Re: Cpu write back cache causing issues.

Posted on 2023-07-13, 17:16

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks. Yeah. The chipset seems to have many names. Seen it being called expertchip, winbond or that symphony wagner. Do you happen to know if there would be a compatible EEPROM chip that I could use instead of the original EPROM for bios on that motherboard? The original EPROM seems to be TMS …

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Re: ATC-5200 + k6-2+

Posted on 2023-07-13, 13:41

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Well, found some clear-ish pic on an aliexpress listing, but still can't see the regulator IC clear enough to be sure.. https://www.aliexpress.com/item/1005004038474240.html currently suspecting the tiny little 8 pin thing underneath the bottom toroid coil, under the CPU socket. Thank you …

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Re: Cpu write back cache causing issues.

Posted on 2023-07-13, 11:31

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks for the v2.3 BIOS dump. A first look to the CPUID tables with a hexeditor shows the expected Enhanced Am486DX2/4 support, but no Am5x86 support. But when checking this BIOS with Award’s Modbin tool, I found a hidden “Internal Cache WB/WT” option that was fixed at “Write Thru”. So unless this …

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Re: Cpu write back cache causing issues.

Posted on 2023-07-12, 14:18

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

How does this apply with 2 motherboards having exactly same symptoms including system freezing when trying to slow down the system using turbo button when in WB more? Especially when one of them is PCI motherboard and the other one is VLB motherboard? The LS-486E PCI motherboard was made in 1996 …

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Re: Is My DataExpert EXP4044VL BIOS Actively Locking Out Intel DX4 Processors?...

Posted on 2023-07-11, 14:38

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hi Justin and Jake, Intrigued by this Intel DX4 issue, I have been looking in the EXP4044VL Rev. 2.1 BIOS code as well. What I found was a regular code base for an Award 09/1994 BIOS with CPU support for all 486 models of that era. This includes support for the iDX4-100. However, L1 cache WB mode in …

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Re: ATC-5200 + k6-2+

Posted on 2023-07-09, 10:31

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

See if this is correct: IMG-20230708-WA0815.jpg Oh, I guessed wrong about the position of the Vcore controller IC. This 74F240 is a buffer IC, probably for the ISA-bus. ;) Looking at the motherboard picture on TheRetroWeb, I see a likely candidate at the other side of the CPU socket, near the edge …

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Re: ATC-5200 + k6-2+

Posted on 2023-07-08, 21:17

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

That would be the little chip between the first ISA slot and the corner of the CPU socket.

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Re: ATC-5200 + k6-2+

Posted on 2023-07-08, 19:57

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Guys, so far everything normal, I've run some games and even used setmul on it, I would like to thank everyone who could help me you are the best. thanks You’re welcome. :) But still one question though: What is the voltage regulator chip on this ATC-5200 board? With this knowledge I should be able …

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Re: ATC-5200 + k6-2+

Posted on 2023-07-07, 18:54

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hi brunofbrsilva, The K6-2+ is a Dual voltage CPU, just like the regular K6-2. Single Voltage CPUs like the original Pentium, the AMD K5, and the IDT Winchip C6, use the same voltage for Vi/o and Vcore. For Dual Voltage CPUs, Vi/o and Vcore are different. This motherboard supports both Single and …

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Re: ASUS TX97-XV (HP OEM) BIOS. Is there a retail BIOS that will work with the HP OEM board?

Posted on 2023-07-07, 17:34

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Okay, here is the patched Asus TX97-XV BIOS. It is a modded version of the latest 0112xv-1 retail Award BIOS. In the zip, a PATCH.TXT file is included that documents all the changes I’ve made to this BIOS. 0112xvj2.zip Like the Award retail BIOS, this patched version also needs to be programmed in …

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Re: ATC-5200 + k6-2+

Posted on 2023-07-07, 16:57

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

About the BIOS on your ATC-5200 v1, yes you need the latest Ver. 1.0 08 (01/26/2000) BIOS for your K6-2+/550. This Ver. 1.0 08 BIOS fully supports the K6-2+ and K6-III+ CPU and also has IDE HDD support up to 128GiB. :) All earlier BIOS versions do not support your K6-2+ and are limited to 32GB …

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Re: Iwill xa 100 motherboard

Posted on 2023-07-06, 18:09

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hi Tomcattech, I have this nice ATX Super Socket 7 board and it is a good performer. Its running a K6-2/500 rock solid, and a first test with a K6-2+/450 at 550MHz looks promising. My XA100 is PCB Ver 1.10. Note that the latest 07/20/1999 BIOS version 32210 at https://theretroweb.com/motherboards/s/ …

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Re: ASUS TX97-XV (HP OEM) BIOS. Is there a retail BIOS that will work with the HP OEM board?

Posted on 2023-07-05, 10:19

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hi pico1180, Because there is an HP Phoenix BIOS on the board now, any Asus flash tool will be unable to flash the Asus Award BIOS. So using a programmer like your TL866Ⅱ Plus is indeed the only way to get the retail BIOS from Asus on this TX97-XV board. However HP is using a 256KB EEPROM on this …

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Re: Jamicon KM-S4-1 / Rectron RT-4S3 Bios update

Posted on 2023-07-02, 14:51

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

egbertjan wrote on 2023-07-01, 14:10: Thank you very much Jan, you are very herlpfull. I indeed live in the Netherlands, in Drenthe. I would appriciate it very much if you could help with updating the BIOS. Can you let me know what steps I have to take? Egbert Jan Okay, I send you a PM with the …

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Re: The patched K6plus BIOS repository gets a new home!

Posted on 2023-07-01, 14:15

by

by Chkcpu

in Release Announcements

in Release Announcements

Thank you all for the nice words. 😀 I just noticed that the redirect from the old to the new url doesn't work anymore. So my website is now only available via the new url: http://www.steunebrink.info/ Cheers, Jan

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Re: Jamicon KM-S4-1 / Rectron RT-4S3 Bios update

Posted on 2023-07-01, 08:57

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

@TheMobRules, thanks. Yes this BIOS chip is indeed an UV-EPROM. This M27C1001 by SGS-Thomson is a 1Mbit (128KB) EPROM and was widely used on boards of that era. Here is its datasheet: M27C1001.pdf This EPROM needs a programming voltage of 12.75V, so most (E)EPROM programmers will support this chip. …

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Re: Trying to use a K6-2+/3+ in an OrangePC 620 PC compatibility card.

Posted on 2023-06-30, 17:43

by

by Chkcpu

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Ok so I tried the modified bios just now and at a 2x multiplier I am getting 256mhz on a K6-2/450AFX Other OPC620 users reported the same erroneous 256MHz indication when using the 2.0x = 6.0x multiplier setting on the stock BIOS with a K6-2 or K6-III. However the patched BIOS indicates the correct …

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