Re: Cyrix DX2-80 slower than DX2-66?

Posted on 2020-07-12, 22:04

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Yeah, good luck on finding UMC chipset data sheets. If your BIOS is AMI, you might want to try AMISETUP to get access to hidden configuration options. If your BIOS is AWARD; you might want to try MODBIN to create a modified BIOS for your board that exposes more configuration options. MODBIN is a …

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Re: Cyrix DX2-80 slower than DX2-66?

Posted on 2020-07-12, 21:58

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The memory graph seems to indicate that I indeed was right about "chipset autoconfiguration" being the cause of the problem, but I explained about L2 timings, whereas the problem is in fact about main memory timing. (Nearly?) all 486 consumer boards derive the memory timing (how long to wait after …

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Re: CMOS Inoperational - System Halted

Posted on 2020-07-12, 04:33

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Oh, searching for the error I happened upon this: (Solved) Bios POST error message: CMOS INOPERATIONAL. SYSTEM HALTED.

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Re: CMOS Inoperational - System Halted

Posted on 2020-07-12, 04:26

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Funny that you mention finding it in the street. When I was middle school aged I found a 486 on the side of the road. Ended up putting Win95 on it and giving it away to a neighborhood kid who had no computer at home. Maybe this thing has some kind of sanity check where it's noticing the CMOS not …

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Re: 486DX2 heat sink debate

Posted on 2020-07-12, 03:58

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Anything above 25Mhz needs a heatsink. Not really. Yes, even if taken in context. I'm not really interested in your opinion of my opinion. Shocking, I'm sure. Hopefully you also liked johnnycontrario's analysis. I liked his scientific approach. It seems what Intel is telling us in their datasheet …

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Re: 486DX2 heat sink debate

Posted on 2020-07-12, 00:49

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks for the detailed analysis. It seems you're coming down pretty strong on the side of an Intel 486DX2-66 needs a heatsink and fan, or if no fan, a ginormous heatsink. I had only one system with a stock 486DX2-66 and I barely remember it, but I believe it had a small heatsink and no fan.

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Re: 8bit ISA ethernet card or parallel/ethernet converter?

Posted on 2020-07-11, 23:43

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Don't forget about PLIP, too, in a pinch. It uses a LapLink cable so that you can connect to another computer's parallel port and it emulates an Ethernet card. It can run about 4x as fast as 115,200 serial but I don't know how well it would do on a 386.

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Re: 486DX2 heat sink debate

Posted on 2020-07-11, 19:34

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Weird, could your DX2-80 be a phony? 😜

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Re: 486DX2 heat sink debate

Posted on 2020-07-11, 19:12

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I've got a AMD DX2 -80 which despite being listed as a 2x multiplier part (and I was anticipating running a 40MHz system bus) is actually a 3x multiplier, so using a 25MHz system bus is needed to get it to identify as a DX2-80 in DOS (and even then it's actually 75MHz). Anyway I've put a Socket 370 …

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Re: 440BX Pentium 3 System Won't Boot, No Video

Posted on 2020-07-11, 18:51

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

That's a good point about maybe it's an AGP issue and you have no way to know since you have no PC speaker and no POST code reader. Here's hoping it's beeping something at you that you just have no way to detect. I got rid of a ton of the retro stuff I had originally in the late 90s/2000s but I'm …

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Re: Cyrix DX2-80 slower than DX2-66?

Posted on 2020-07-11, 18:49

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

When "upgrading" from a DX2-66 to a DX2-80 I noticed a drop in performance. I suspect it might have something to do with the required jumper settings for the 80MHz processor, because it requires to be set up for a 40MHz processor and then the CPU is responsible for its own internal clock. The BIOS …

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Re: Cyrix DX2-80 slower than DX2-66?

Posted on 2020-07-11, 18:43

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Do you run the Cyrix' L1 cache in write back or write through mode? I've got a motherboard that allows Cyrix processors (the older ones without "standard pinout") to be operated in L1 write back, same with Pentium overdrive. However, all other socket 3 processors can only be operated in L1 write …

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Re: Cyrix DX2-80 slower than DX2-66?

Posted on 2020-07-11, 18:41

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I don't know how your motherboard handles wait states. Usually the VLB wait state will be set by a jumper on the motherboard. Memory wait states on 486 boards are normally set in the BIOS, but I have seen some older 486 designs that used jumpers. Sometimes the memory wait state jumpers are "hidden" …

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Re: Cyrix DX2-80 slower than DX2-66?

Posted on 2020-07-11, 05:12

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I noticed similar with my St dx2-80 aka cyrix, in Doom and 3d bench it scores slightly slower than the dx2-66 from Intel I had. I'm keeping it though because everyone does Intel or maybe and, but who does an ST 486. Do you think it's just that Cyrix was the half-baked cheap option, or it's indeed …

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Re: Retro builds with modern conveniences

Posted on 2020-07-11, 03:24

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I love the sound of an old floppy doing a Seek on bootup on an old sytem. There is something magical about that at my age that is just great, of course any one below 40 probably hates that sound because they never grew up with it or cannot remember it. To each their own ! Well, some of are below 40 …

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Re: 440BX Pentium 3 System Won't Boot, No Video

Posted on 2020-07-11, 02:42

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hello! A 440BX board with Pentium III is also what I set up when I got into old stuff. One way or another you're going to need a PC speaker attached or this is going to be a world of frustration. Could you attach a picture of the RAM. I wonder if you are running into the low vs. high density issue. …

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Re: Cyrix DX2-80 slower than DX2-66?

Posted on 2020-07-11, 02:27

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I'm playing with an Intel DX2-66 and a Cx486DX2-80 and seeing a similar situation. When I set the bus speed to 40MHz but leave the VLB jumper on <= 33 MHz and CPU speed jumper on <= 33 MHz, the numbers in Speedsys for memory reads bigger than 256kb (my cache size) get worse than the DX2-66. The …

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Re: What are the best retro ISA and PCI slot network cards?

Posted on 2020-07-10, 01:22

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

So there's no DOS packet driver for this card, damn... What a shame i really like it, its really small and slim, goes really well with the AWE Upgrade card on the shared PCI/ISA slot. I mainly use mTCP for networking in DOS, really disappointed i cannot use it. I tried the Intel EtherExpress 100 …

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Re: What are the best retro ISA and PCI slot network cards?

Posted on 2020-07-10, 00:06

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I've got an RTL8169 gigabit card with Windows 98SE drivers.

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Re: 486 vs Pentium for a Retro build

Posted on 2020-07-10, 00:03

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Would part of the answer to this be, if DOS games are involved, whatever gives you the most upper memory?

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