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High_Treason
November 2nd, 2013, 11:48 PM
I'm kinda stuck, figured I'd ask some opinions (and likely, being the rebel I am, ignoring them and doing the opposite of whatever they say) - those opinions being on what to do with a bunch of hardware that is now doing nothing. I want a machine in the Pentium 60-75 performance band as my current 486's are too slow and my Pentium (and K5) are too fast.

I had my 5x86 running reasonably with only a cache problem (Hotflashed BIOS to something I don't remember, never hotflashed before, it was fun) but it's blown the transistor again and I am not repairing the board again as I have learned there are about 10 different versions of the same board and found two people that had the same problem, other people had similar problems to me with RAM and such. Might be worth pointing out a variant of the board was the PCChips M921 (http://motherboards.mbarron.net/models/486pci/m921.htm), mine is halfway between that and the SYL8884PCI (http://motherboards.mbarron.net/models/486pci/syl8884.htm)... Might explain the cache issue anyway though it did have real cache that partially worked. Mine is labeled Topsearh Elpina but the BIOS chip has M921 printed under the AMI label.

What I have left over is;
> Pro AudioSpectrum Plus (This thing is awesome)
> S3 Trio 32
> A stack of FPDRAM (Four 16MB sticks, two may be faulty)
> A couple of 4GB CF Cards
> Other generic early 90's PC parts that are homeless as this is likely my last Pre-6th-gen build.

Generally this thing is there to fill the gap between the slow 486-class and fast Pentium-class machines and provide a medium between the two, it would be useful for playing things like Doom clones and a few Windows games (mostly adventure games) not to mention it should prevent timing problems in certain demos and games whilst performing fast enough (again, my current fastest 486 is a bit slow and the K5 is far too quick).

I am torn between getting a Pentium 60 or another 5x86 motherboard (it'd be the third one) for this, both cost around the same so that's not an object. My argument for both is this;

5x86
I invested a lot of time and money into it already, it seems a shame to waste a perfectly good CPU and I've got the potential to have VLB cards as well which are an interesting relic.

Pentium
The 5x86 is known to be unstable and unreliable, I don't have any pre-Socket 7 Pentiums anymore (the last one was sold some years back when I was broke) and I suspect it'd handle better in Windows.


This time, both boards are from respectable manafacturers, would have cost a lot back in the day. I have a feeling the fact that Weird Al's "All about the Pentiums" playing in my head is trying to tell me something, but what do you think?

Jorg
November 3rd, 2013, 12:12 AM
If I look what I found usable most for me I still find that I'm most happy in this range with my Asus P/I-P55TP4 (http://support.asus.com/download.aspx?SLanguage=en&p=1&s=5&m=P%2fI-P55TP4%28XE%29%28XEG%29&os=&hashedid=n%2fa) and Pentium 90/ P54C.
This has a 430HX chipset, takes FPM and EDO Ram, and is just rock stable. Having both PCI and ISA slots is a good thing too.
If you want you can clock it down to 50Mhz.

Everything in between this and standard 486/33 (or DX2/66) is very nice for tinkering around (lots-a-jumpers!) and 'special considerations' (VLB bus speeds with 2 cards, bios for Cyrix M1, 3x33 or 2x50 Mhz choices, etc) - but can drive you nuts if you want usability.

I still kept this board from when I got it as main machine early 90's, and its still going well.

k2x4b524[
November 3rd, 2013, 12:52 AM
PC Chips M919 is a very good board with the 5x86, can take 128mb ram, has a vlb slot, pci slots and the standard compliment of ISA, plus all the standard multi i/o goodies. If you've actually got cache module made for that board, i envy you, but without the cache, and fed a 5x86, it will perform in the pentium 60 to 75 range an in some cases, it can compare to a pentium 90. I recently setup an M919 i acquired from a gent on this forum. Hell the board even takes my 486 DX-50 without a hitch..

Unknown_K
November 3rd, 2013, 01:19 AM
I found last generation PCI (only PCI not combo PCI and VLB) 486 boards were very stable. I ran a 486/133 at 160 for years on a PCI board (100% stable). You also get lucky being able to use 72 pin SIMMs which are still common. Also early PCI video cards are still available cheaply with a wide selection of types.

Agent Orange
November 3rd, 2013, 08:29 AM
I'm kinda stuck, figured I'd ask some opinions (and likely, being the rebel I am, ignoring them and doing the opposite of whatever they say) - those opinions being on what to do with a bunch of hardware that is now doing nothing. I want a machine in the Pentium 60-75 performance band as my current 486's are too slow and my Pentium (and K5) are too fast.

I had my 5x86 running reasonably with only a cache problem (Hotflashed BIOS to something I don't remember, never hotflashed before, it was fun) but it's blown the transistor again and I am not repairing the board again as I have learned there are about 10 different versions of the same board and found two people that had the same problem, other people had similar problems to me with RAM and such. Might be worth pointing out a variant of the board was the PCChips M921 (http://motherboards.mbarron.net/models/486pci/m921.htm), mine is halfway between that and the SYL8884PCI (http://motherboards.mbarron.net/models/486pci/syl8884.htm)... Might explain the cache issue anyway though it did have real cache that partially worked. Mine is labeled Topsearh Elpina but the BIOS chip has M921 printed under the AMI label.

What I have left over is;
> Pro AudioSpectrum Plus (This thing is awesome)
> S3 Trio 32
> A stack of FPDRAM (Four 16MB sticks, two may be faulty)
> A couple of 4GB CF Cards
> Other generic early 90's PC parts that are homeless as this is likely my last Pre-6th-gen build.

Generally this thing is there to fill the gap between the slow 486-class and fast Pentium-class machines and provide a medium between the two, it would be useful for playing things like Doom clones and a few Windows games (mostly adventure games) not to mention it should prevent timing problems in certain demos and games whilst performing fast enough (again, my current fastest 486 is a bit slow and the K5 is far too quick).

I am torn between getting a Pentium 60 or another 5x86 motherboard (it'd be the third one) for this, both cost around the same so that's not an object. My argument for both is this;

5x86
I invested a lot of time and money into it already, it seems a shame to waste a perfectly good CPU and I've got the potential to have VLB cards as well which are an interesting relic.

Pentium
The 5x86 is known to be unstable and unreliable, I don't have any pre-Socket 7 Pentiums anymore (the last one was sold some years back when I was broke) and I suspect it'd handle better in Windows.


This time, both boards are from respectable manafacturers, would have cost a lot back in the day. I have a feeling the fact that Weird Al's "All about the Pentiums" playing in my head is trying to tell me something, but what do you think?

3 years ago or so, I was actively in the 486 business, just a little more than I am now. I had a POD 83 in a 486 mobo and found I had more compatibility issues than I wanted to deal with at that time. The POD series was known to have its quirks. You may want to check out this old forum link. http://www.vintage-computer.com/vcforum/archive/index.php/t-20615.html




i

High_Treason
November 4th, 2013, 02:40 AM
Thanks to all who gave an opinion on this, it did help me make my mind up in some round-about way. After much thought and consideration, I have decided to scrap the 5x86 for the time being, I have also decided that I may resume that one at a later date. Motherboards to support the 5x86 seem to pop up often at reasonable prices but Socket 4's seem to be rising in price and disappearing from the market. Also potential compatibility issues have swayed me. This cost more that I would like, my bank account is now only in double figures, but the motherboard is built by Intel and so I know it is likely to function correctly (Intel's boards are boring, but I never had one that didn't work) and comes with CPU and RAM. This is what I have bought;
http://www.amoretro.de/ebay/2013/06/batman_1.jpg

It comes with an Intel Pentium 60 and 16 MB RAM, also has a modded dallas chip so it should be good for a few years (no idea how long the rest of the chip lasts for, never had one fail yet) - that CPU has the FDIV bug as far as I know, hopefully that doesn't cause me any problems, though I don't think I'll be running much on there that uses the FPU. I do expect the 16-Bit integer performance to lag behind the 5x86 a little but I don't actually know for certain how different it will be yet.

Here's hoping everything works this time, if it turns out good I might ditch that Trio and get a nice video card for it.


On the price again, this seems to be the cheapest with a CPU and actually cheaper than any I could find without after shipping, as it's from Germany and all others were from US/Canada. Of course availability might differ elsewhere in the world, it's not easy to find pre-Super7 stuff where I am.

Stone
November 4th, 2013, 03:39 AM
Keep an eye on those electrolytic cans. I have a stack of boards from that era and none of them works. I think they all need to be recapped! Those cans are a real PITA!

RWallmow
November 5th, 2013, 09:20 AM
Keep an eye on those electrolytic cans. I have a stack of boards from that era and none of them works. I think they all need to be recapped! Those cans are a real PITA!

Those ones between the slots look like they would be a real pain to replace, not a lot of room to work. For the record I have a VERY similar board to that (similar vintage socket 4 made by Zeos), I am NOT looking forward to having to recap it, for now it looks good though, works great and caps are NOT leaking or failed.

Stone
November 5th, 2013, 09:59 AM
Those ones between the slots look like they would be a real pain to replace,...
Man, they're *all* a real pain to replace!!! Why do you think I have a stack of otherwise good boards including two which are my favorite, (2) ECS K7S5A and (2) DFI K6XV3+/66 which happens to have (1) AGP, (3) ISA, and (4) PCI slots. This particular board is SUPER tweener material!

RWallmow
November 5th, 2013, 10:13 AM
Man, they're *all* a real pain to replace!!! Why do you think I have a stack of otherwise good boards including two which are my favorite, (2) ECS K7S5A and (2) DFI K6XV3+/66 which happens to have (1) AGP, (3) ISA, and (4) PCI slots. This particular board is SUPER tweener material!

While I wouldn't call it fun, its not SO bad if they are not too cramped in there, I have recapped quite a few now (SE/30, 2 or 3 P4's and an Athlon rig), with a few others on-bench waiting too. The worst I have done was my Mac Powerbook 100, that was cramped and unpleasant, and its not even done yet, my soldering iron crapped out mid-recap :crazy:

Anonymous Coward
November 5th, 2013, 06:54 PM
I really enjoy systems based on the Cyrix 5x86 chip. Am5x86s are pretty good too. At this point in time I would probably recommend a Pentium however. 486 motherboards are pretty expensive, and quite frankly many of the PCI variants just aren't very good. Only the very last PCI 486 motherboards were any good, and it can be very hard to distinguish them from the flaky ones as you have to pay attention to the chipset production dates and steppings.

I'd go with a Pentium based on any of the intel Triton chipsets (VX, HX and TX). In reality they're all about about the same speed, though the HX is *slightly* faster I'm told. The differences are mainly in which types and amounts of memory they can accept (and how much is cached), UDMA33 and USB support. If you are running DOS on these machines, none of that really matters though.