Re: Fast Pentium MMX compared to a Pentium II

Posted on 2023-06-05, 18:55

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Further update with a few more Mendocino CPUs and an AMD K5. For some reason K5 refuses to boot @ PR200 clock on this motherboard, works fine on older motherboards with a linear voltage regulator /shrugs.

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Re: Fast Pentium MMX compared to a Pentium II

Posted on 2023-06-03, 17:36

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I have updated original post with more results from Celeron Covington/Mendocino, PII Deschutes CPUs at different frequencies, also included Pentium MMX @233MHz. Now we can see that a 300MHz Klamath @66MHz FSB and with lowered RAM timings now performs essentially the same as a 500MHz AMD K6-2 on a …

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Re: Fast Pentium MMX compared to a Pentium II

Posted on 2023-06-02, 23:01

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The main goal of this comparison was to determine the equivalent performance of a P6-class CPU compared to a P5-class CPU, that is pushed to its limits on a period correct socket 7 motherboard. I could redo the benchmark at a stock 233MHz or much slower Pentiums/K5s/K6s/Cyrix 6x86s, just point out …

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Fast Pentium MMX compared to a Pentium II

Posted on 2023-06-02, 20:23

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I have long wanted to know how a heavily tweaked Pentium MMX system, from the year of 1997, would compare to Pentium II systems of the time. I recently had the opportunity to build one such Pentium MMX PC, tweak and test it :) Specs of the Pentium MMX system: MB - ASUS VX97 w/buck converter, i430VX, …

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Re: Can't get L2 cache work in UM486V motherboard when am5x86 CPU is inserted

Posted on 2023-05-18, 19:26

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

After the am5x86 CPU upgrade in the PCI 486 system with a more stable one, I had the old one lying around unused for a while, so I decided to take another look at the am5x86 and UM82C480 chipset incompatibility problem with the L2 cache. My previous assumption, that the chipset is the main cause of …

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Re: NOS Trinitron has small flaw

Posted on 2023-02-16, 02:32

by

by SSTV2

in Marvin \ Video

in Marvin \ Video

Degauss it with an external magnet 😉

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Re: AT PSU suggestions

Posted on 2023-02-16, 02:24

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I wouldn't rule out the modification option. By default, 220V voltage power supply units can be modified for the 110V electrical system just by installing a single jumper wire. 220V-only PSUs often have unused 115/230V switch solder pads marked on the PCB as "SW" that need to be connected. From a …

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Re: Original Voodoo 5 6000 prototype for sale on eBay

Posted on 2023-02-13, 04:00

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Indeed that was ...

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Re: I recently found this hardware, AKA the Dumpster find thread.

Posted on 2023-01-01, 17:27

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Found this little motherboard last week. Seems to have suffered some damage. Do you think it will be fixable ? https://theretroweb.com/motherboards/s/soyo-sy-5ehm Spoiler just kidding, This will be only for parts If nothing else, apart VRM, is damaged, you could still make it run, just source …

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Re: um82c865f datasheet needed

Posted on 2023-01-01, 17:12

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Perhaps a -12V rail is absent?

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Re: Compaq Armada 1550DMT fun.

Posted on 2023-01-01, 17:08

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Sphere478 wrote on 2022-12-31, 22:44: Re: Multiplier Bodge Board For laptops 486, Pentium, K6 , Cyrix. Made this for it 😀 But the P54C's BF pins are internally pulled-up.

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Re: Help anyone with IBM PS2 and XGA card on MCA bus

Posted on 2022-12-29, 18:57

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You probably have already noticed what XGA-2 adapter I have from this post, but to make sure there are no doubts - it's the first revision with a heatsinked RAMDAC (part number should be 33G0327ESD ) I have dumped the first 8KB of the UMA's C segment, where the XGA-2 BIOS is mapped on my machine. …

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Re: Help anyone with IBM PS2 and XGA card on MCA bus

Posted on 2022-12-28, 14:45

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I tried emulating an ESDI controller instead of SCSI, but the XGA-2 BIOS still wouldn't get resources allocated, for some reason you're not even allowed to change the ROM address range. However, I noticed one discrepancy when changing the address range of the SCSI ROM - it gets assigned 8000H (32KB) …

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Re: Help anyone with IBM PS2 and XGA card on MCA bus

Posted on 2022-12-28, 02:16

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You are welcome, keep up the good work ;) Out of curiosity, I created a virtual IBM PS/2 Model 80 in the "86Box" and enabled the XGA-2 adapter in the options. The first thing I encountered, when installing XGA-2 from the reference diskette, was a resource conflict, which manifested as an inability …

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Re: Help anyone with IBM PS2 and XGA card on MCA bus

Posted on 2022-12-27, 21:10

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I had a suspicion that it reads register values off an XGA adapter on an XGA-2 machine, this time values are different: XGA2 Index 52H value: 21FA; XGA2 Index 53H value: 2153.

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Re: Help anyone with IBM PS2 and XGA card on MCA bus

Posted on 2022-12-27, 18:29

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Just ran all of the provided tests on both machines and the following results were obtained: XGA machine: COMPID.EXE - Model: Unknown; PS2BUS.EXE - PoC: MC Bus; XGARD52H.EXE - Index 52H value: 21EA; XGARD53H.EXE - Index 53H value: 2130. XGA-2 machine: COMPID.EXE - Model: Unknown; PS2BUS .EXE - PoC: …

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Re: Help anyone with IBM PS2 and XGA card on MCA bus

Posted on 2022-12-26, 23:48

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

let's hope it will output "FAIL" in "DMQS not supported" machines and "GOOD" in "DMQS supported" machine The result was exactly that - FAIL on the XGA and PASS on the XGA-2 graphics adapter. Adding full logs of both machines, some notes on hardware setup for completeness: PS/2 with an XGA-2: -Uses …

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Re: Help anyone with IBM PS2 and XGA card on MCA bus

Posted on 2022-12-26, 20:02

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hi, I'm adding log files, collected from two separate Model 90 XP's. File "XGA.LOG" is generated by a PS/2 with an integrated XGA adapter, while "XGA-2.LOG" is generated by a PS/2 with an early XGA-2 adapter (heatsinked RAMDAC). XGA: Video Functionality/State Information …

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Re: DOS start up sound

Posted on 2022-12-21, 15:13

by

by SSTV2

in Marvin \ Sound

in Marvin \ Sound

I would use exactly this as the startup sound on my ripened cheddar 😐

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Re: Compaq Armada 1550DMT fun.

Posted on 2022-12-19, 15:01

by

by SSTV2

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Where you able to find the datasheet for the MK1491-01 to ID the FSB resistors? Out of curiousity I had a quick look and I've only been able to find the -06, -09 and -14, and they're all very different (e.g. the -09 swaps the pin 1&4 Gnd and Vdd compared with the -06). Unfortunately, I could not …

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