Something Random

sedrosken

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You end up with strange issues with older machines. In another effort to get just a little more performance out of my 486 -- I really, really just wanted to see Diablo play smoothly on it, and seeing 32-channel XM modules play smoothly would be nice as well -- I've managed to source a few PGA168 interposers that offer a way to force a 3/4x multiplier for boards without support for that, and voltage regulation to take the 5v the board provides down to the 3.3v that won't fry newer CPUs. I used the Am5x86 I'd previously used with the M912 board, and thankfully it's not fried -- initially I had the sort of success that I never do, everything just worked. CPU-Z made the thing BSOD, but that was actually down to the VxD it generated to get access to the CPUID I suppose -- deleting the old one and letting it remake it solved it.

No, I dipped back into the case and noticed I had some residue on the AA batteries where I'd superglued the holder to the power supply in lieu of using less-permanent mounting options, as the others I'd tried lost their adhesion after a while. Without thinking I removed the batteries to clean this off, and lost all my CMOS settings. When going through and resetting all those settings, I have a few that actually have a reputation for being unstable on this class of hardware; namely, I have everything (cache, RAM, local bus) set to zero wait-states, and I'm both shadowing and caching an option ROM at address D000-D7FF. You can see why I initially thought one of these other settings must have been causing the problems I'll describe in a moment -- they are known to cause instability on other 486-class machines, and while they worked reliably here before, maybe something changed with the upgrade I did.

When booting, particularly in my normal configuration loading EMM386 and then initializing my sound card at address 220h, interrupt 5, low DMA 1, and high DMA 5, with the MIDI port at 330h, the machine would totally freak out, drop to 40-column text mode, and then display an error message that seemed pretty unsure of itself:

"MEMORY PARITY ERROR ????"

It turns out that I'd inadvertently toggled the Gate A20 Emulation setting from Chipset to Fast. For those unfamiliar, this dictates how expanded memory is accessed, and as most 386+ DOS configs make use of EMM386 to provide expanded memory emulation using extended memory for applications requiring it, it's a surprisingly important setting. On later machines I'm sure this works fine in Fast mode, indeed I remember it causing no issues back when I had the Pentium Pro machine. However I'm guessing that the UM480, being a combination 386/486 chipset made at a time when some people still used genuine expanded memory cards, might just be early enough that it's got some weird bugs with that mode of operation.

One CMOS setting had the 486 out of commission for weeks between me not having time to diagnose further and simply having no idea what could possibly be wrong. Imagine my terror when swapping back to the DX4 OverDrive, a known-good CPU, didn't fix the problem! I reseated and used deoxit on the contacts of all my RAM and every add-in card, several times, swapped hardware around, and only when I decided to try loading the BIOS defaults on a whim did I fix it purely by accident.

Ironically this is still not the final chapter -- I want to find a specific model of AMD DX4 CPU, one rated for 120MHz operation (so I can use the 40MHz crystal and run a 40MHz system bus) but that only has 8K of L1 cache, as I'm almost completely certain that's what's tripping up the chipset as far as enabling L2 cache -- these later chips all have 16K. When I finally find one of this specific model that doesn't come from China, doesn't cost two hundred dollars, or perhaps both, I'll have one last thing to test. Thankfully I do have the 12ns cache chips floating around from my M912 misadventure, so if/when I get that working I'll have faster cache for 0WS operation at 40MHz.
 

Mercutio

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You might have a better time if you just tracked down an OG 486DX/50 than messing with the 3rd party clock multiplied CPUs. Cyrix and AMD both made absolute garbage in that era, and the reason the DX/50 was so badass that everything else clocked to 50MHz along with the CPU. You'll probably get the best graphics off whatever VLB nonsense you have (ET6000? S3 Trio?) from the bus speed improvement over the extra CPU clock.
 

sedrosken

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My board offers support for a 50MHz bus, but none of the cards I have will work at that speed -- even 40MHz is technically overclocking it. And in benchmarks, the DX2-66 beats the DX-50 in roughly 75% of cases, particularly CPU-bound ones, while a DX4-120 beats it in all possible scenarios -- mostly because the 50MHz machine has ISA video since VLB cards that work at 50MHz are so few and far between that realistically the ones that do wouldn't be paired with a DX1 anyway. Because of the way VLB works -- essentially mapping the device and its associated memory directly into the 486 processor's memory map, and with the 486 not really being designed to directly drive devices like this, the generally accepted order of operations is as follows:

- At 50MHz, you'll get one card to work if you're lucky -- usually you'll need to throw a waitstate or two at it.
- At 40MHz, with careful selection and maybe a waitstate for good measure you'll get two cards working -- I just so happen to have two cards that are known to work fine together at that clock, with no waitstates, even! I have a Trio64V+ and a UM8672-based IDE controller. (You're probably thinking of the ET4000/W32p, Merc, the ET6000 was a purely PCI card.)
- At 33MHz, you tend to be able to use all three slots with no waitstates. This is the "design" frequency of the bus, it's what most cards were made to target. Seeing how most people only ever went up to a DX2-66 and then directly onward to a Pentium or some other such, that's about right. Remember, VLB was only supposed to fill the gap until PCI was finished up and ready to go -- that companies continued to make cards following the spec even into 1995 was something of a miracle.
- At 25MHz, the bus is technically underclocked, so if your hardware doesn't even work at this bus speed, it's time to consider other boards.

As for the AMD/Cyrix parts being inferior -- in the Pentium era, that's largely true, and the Cyrix 486s are a bit behind particularly in floating point here, but the AMD stuff is pretty much identical. To the point they got sued for using some Intel microcode, even. The main difference is that outside the DX/SX-40, Intel never bothered making another 40MHz bus part again because of the issues they ran into, and the DX-50 was a rare bird indeed. Usually only found in systems crippled with ISA-only motherboards. AMD and Cyrix both tried their hand at a DX2-80, and again ran into issues mostly stemming from VLB instability, by this point the boards were plenty capable of going that fast. With the DX4-120 that AMD put out, the issues largely disappeared because most people used these on PCI motherboards or newer VLB boards that could cope with the overclock. The Am5x86 only ever officially ran at 4x33 for 133MHz, in parts that people actually got their hands on anyway, but they are well documented to generally be capable of 3x50 for 150 and 4x40 for 160MHz respectively, some models being better for this than others. A couple brave souls drove the record for the 486 platform up to 200MHz by running at 4x50. Interestingly the Cyrix 5x86 part was actually a cut-down 6x86, and it was easily the most advanced (and thus most incompatible and fussy) chip for the socket as a result. Generally it scores pretty disappointingly in benchmarks, even with all the special features enabled it is still generally outrun by a Pentium OverDrive. In actual use I'm told it's actually about as good as its big brother under Windows 9x.
 
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LunarMist

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The 486 DX-50 was not rare as far as I recall. There was a small room full of them at one site in the early 90s. Heavy lifting was done by a couple of Alpha (DEC) systems that the likes of me were not allowed to touch. I had to use a 386. Nobody in MIS would buy any x86 systems that were not Intel. The off-brands were mostly for cheap home systems or quite small businesses.
 

sdbardwick

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The 486 DX-50 was not rare as far as I recall. There was a small room full of them at one site in the early 90s. Heavy lifting was done by a couple of Alpha (DEC) systems that the likes of me were not allowed to touch. I had to use a 386. Nobody in MIS would buy any x86 systems that were not Intel. The off-brands were mostly for cheap home systems or quite small businesses.
DX-50s were rather rare. Fussy with motherboards due to clock and being quickly followed by DX2-66s that worked well with many boards. I think I still have mine around somewhere, along with some AMD DX4s and Cyrix chips (just kept the CPUs for fun, didn't keep the bulky components).

Tannin agrees with rarity:
A very rare bird indeed. In theory, the DX-50 should have been a winner, with 50MHz processing power and a 50MHz bus too, but in practice it was just too fast for motherboards to cope with. We sold only one of them, and had no end of trouble with it. In the end, we gave up changing motherboards yet again and clocked it back to 40MHz, making up the speed difference by going to the (then new) VESA local bus video and I/O cards. (40MHz and VESA — and there is another batch of epic struggles to recount — but this particular one was kind to us.)
Actually, VESA had a lot to do with the market failure of the DX-50. It was hard to make an ISA system run reliably at 50MHz, and almost impossible with VESA. PCI wasn't out then, and when it did come out it was dreadfully unreliable for the first year or so. By the time of the Pentium 75, 50MHz and even 66MHz bus speed was easily achievable: in the time of the 486DX-50 though, 40MHz was tricky stuff and 50MHz boards were a nightmare
 

Mercutio

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Yes I misremembered the ET6000. I have it in my head that Tseng Labs didn't survive into the PCI era.

The rarity might've been an Aussie issue though. I definitely built a few systems using DX/50s. I was in my late teens then, but I had no trouble ordering or assembling systems with them. Beats me what board I used. Might've been Octek or Zeos or Micronics at the time. My bread and butter were the DX/33s, and I recall being very happy with 2MB ET4000 video cards (they allowed for 1280x1024 32bpp in Windows or OS/2) and upselling 17" monitors, which were just starting to be affordable in 1993. I remember getting wholesale Mag Innovision DX17Fs for something like $550 at a point in time that 14" screens were still going for around $150, but the difference was big enough that I could find people who would pay for it, since big box stores weren't even offering "large" displays at the time. Home computing as a weird thing in the early 90s, with a lot of the focus being on getting a Multimedia PC that had both a sound card and a CD-ROM drive. For a while, the NEC drives I was buying actually included a bundle of CDs and a 40 minute VHS tape that explained how to install one! I still have a box from one around somewhere. I remember sound cards as the biggest pain in my ass for a couple years, and being pretty insistent that anyone who wanted a modem get an external one so I wouldn't have to deal with COM3/4 headaches.

From what I remember, both Cyrix and AMD were notorious for getting hot, although Cyrix was by reputation the worst of it.
 

sedrosken

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Yes I misremembered the ET6000. I have it in my head that Tseng Labs didn't survive into the PCI era.

Yeah, the ET4000/W32p was their first PCI-capable chipset, though it apparently wasn't particularly fast on PCI like it was on VLB. The ET6000 was very nice for the time, but given the choice we have today, I'd take a Matrox card over an ET6000 every time. The Matrox will be faster, have more stable drivers, and have a much better output quality too. For some reason people don't seem to be hoarding Matrox cards like they are nVidia/ATi stuff so you can actually find one for a decent price these days.

From what I remember, both Cyrix and AMD were notorious for getting hot, although Cyrix was by reputation the worst of it.

That may very well be the case, but I go overboard with my cooling anyway. I have a heatsink that wouldn't be out of place for a mid-level Socket 7 machine installed on my Am5x86, not because it particularly needs it (the thing barely gets warm to the touch), but because I'm paranoid and would like this thing to last ideally as long as I can get it to. I know the Cyrix ones are very hot indeed, because the manufacturing facilities they had access to at the time were, compared to those of AMD and especially Intel, quite primitive. Frankly, if their deal with IBM didn't go through, they probably never would have been able to make the 6x86, and even that had heat problems.

This week in Impulse Purchases™, I snagged a Japanese New 3DS LL (their version of the XL since X isn't used to denote size there) in pretty decent shape. It's going to take a month or so to get here because customs, but once it gets here it's off to the races. I bought the Japanese version because that's easily the cheapest to acquire, the American version starts at roughly twice the price. I can't read a word of Japanese but apparently if you softmod it (and there's a universal exploit that works on every region, every firmware) you only need to blindly navigate the katakana maze once, since the homebrew and all the launchers tend to be in English and the process makes the console region-free. As for why I did this, I've been wanting a 2DS or 3DS since I lost my last one in my breakup with my ex. I didn't have many games for it but I loved what I did have. Plus, the DS backcompat is pretty much perfect aside from the Guitar Hero games that use the grip that attached to the GBA slot, and there's apparently a way to hijack the Virtual Console emulator to run any ROM you want from the consoles it supports, to not even get into the homebrew scene.
 
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Mercutio

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It Could Happen Here is a legitimately interesting podcast. The oldest episodes in the feed are about the ramifications of civil war and the Balkanization of the USA, from a journalist who spent his career in conflict zones like Syria and Georgia and from relevant subject matter experts.
The podcast recently relaunched with an updated focus on climate and the crumbling infrastructure we seem to have in the USA and western world.
Today, the podcast's guest was Chelsea Manning, who discussed practical matters for individual information security. It's worth a listen.
 

Mercutio

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Shang Chi wasn't what I thought it would be. Marvel made a Wuxia movie, akin to Crouching Tiger, Hidden Dragon, by way of both frequent nods to Chinese mythology and the now clearly defined Marvel Cinematic Universe. In comics, Shang Chi was absolutely created to tie in to Bruce Lee and Shaw Brothers in their biggest moment, but rather than play on any of that, we have another sympathetic villain, strong comic relief and some fantastic fight choreography. I really like the way this movie handles color. It's very clear who is who throughout and the action is all the more impressive for how easy it is to follow.

If you have small people to take, yes, it's violent in terms of punching and kicking, but there's no graphic bloodshed.
 

sedrosken

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A bit random, but that's what this topic's for...

What VPS provider would you recommend? I don't want or need anything spectacular, though I could be persuaded to splurge a little if they offer free or cheap domain registration as a bonus. My budget is, like, $30/mo maximum, but that's if it does everything I want -- let me explain.

Bare minimum essential needs are the ability to run ZNC (an IRC bouncer), and an instance of Apache2. I don't expect ridiculous amounts of traffic, in fact the site will be pretty barebones -- HTTP only and HTML3 compliant at best. That can run on any old potato, heck if my ISP didn't go ballistic on people hosting from residential connections I'd consider self-hosting again. I'd prefer no bandwidth cap, just to not have to think about it. The most I'd spend on this basic of a server would be, like, $10/mo.

Nice-to-haves would be 4c/8GB RAM, as then I'd have some breathing room to use on a MariaDB server and a couple game servers, probably just Quake III and an Asheron's Call server. I could probably squeak it by on 4GB/2c, especially since I expect to be the only player, and it'll be console-only anyway, but I'd prefer to not have to do that.

Storage is not a concern. I won't be running a file dump, the biggest space sink will be the logs from ZNC I expect. I've got that running from a free-tier AWS server with an 8GB virtual hard disk and it's barely sitting at half-used all told. As for why I'm unhappy with Amazon, I mostly just don't want to give them any more data than I have to, and I've heard some rumblings that the free tier only lasts about a year or so.
 

sedrosken

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You can disregard this last post. I ended up looking on LowEndBox for a deal and found one with RackNerd -- for 24 dingleberries a year I have a VPS with 2.5GB RAM and 2 cores on an E5-2680v2, with 40GB of space to play with. Plenty for the base usecase I had in mind, we'll see if I can make it work for MariaDB and that AC server. I may just be able to squeak it. I bought a domain on namecheap for all of $1.18 for the entire year. Entire setup, start to finish, with me slamming my face into a brick wall a few times for good measure, took around four hours.
 

Mercutio

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FWIW you should be able to get an AWS instance in that range, but if you can find enough to do with a low-end system like that, you can PROBABLY find enough to move on up to a self-hosted box somewhere. It's not hard to make a VM host on a 1U rack a profit-making item.
 

sedrosken

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Yeah, I was considering repurposing another Sandy Bridge-era Optiplex for that, maybe install a RAID card and drop a few drives in it for RAID5 and use it for a home NAS while also running my website and bouncer from that, but supposedly my new ISP is way stingier about people putting stuff on port 80. Which, I guess, fair enough -- I didn't pay for the commercial connection, after all. Besides, my connection goes down once or twice a night, while it's fine for residential use it's really not ideal for something that's supposed to be up 24/7/365.

The database and game servers would be better used on such a local server as well, but for now, it works, so I'm not going to change anything while I'm still going through some significant changes.
 

Handruin

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Check out Linode for a cheap VPS? That's what's been hosting this site for many years.
 

sedrosken

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I actually ended up with something from RackNerd, they had a special cooperative deal with LowEndBox for a 2.5GB/3c/40GB VPS that I jumped on for I think 24 bucks a year? It's more than adequate for what I need.
 
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