Power Trouble

Posted on December 5, 2019 by Michal Necasek

This will not come as a surprise to anyone who is deeply familiar with PC hardware; the other 99% please bear with me.

A good quality and compatible power supply is crucial to the healthy operation of a PC. The catch is that whether a PSU (Power Supply Unit) is actually compatible and truly good quality may not be very apparent. Even worse, when there are problems, the symptoms may be extremely non-obvious and tend toward “analog” failures—sometimes things work, sometimes they don’t, seemingly with no rhyme or reason.

Probably my favorite retro mainboard is an Alaris Cougar, a VL-bus OEM board manufactured by IBM, also known as IBM Cobalt-AT. The board has an onboard 100 MHz IBM BL3 processor (a triple-clocked Blue Lightning 486DLC, i.e. IBM’s rocket-boosted 386), separate Socket 2 for a 5 Volt 486 SX/DX/DX2 or Pentium Overdrive, a blazingly fast Adaptec VLB IDE controller, and MR BIOS which POSTs about hundred times faster than conventional BIOS implementations (well, not really but it often feels that way, because it is easily 10 times faster).

The board is from 1993 or 1994 and of course it uses the Baby AT form factor, with a classic AT P8/P9 power connector (ever plugged those in backwards? I have…). AT power supplies are getting harder to find and their on/off switches are not suitable for bench operation. An ATX PSU with a switch on the back, combined with a simple ATX to AT adapter, does a better and usually quieter job. Except not always.

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Posted in PC hardware, PC history | 13 Comments

Wireless Networking in DOS

Posted on December 2, 2019 by Michal Necasek

Wireless networking has a long history, longer than most people realize. NCR’s WaveLAN was available in 1990 and of course supported DOS. But WaveLAN was only the precursor to IEEE 802.11 and it is completely incompatible with IEEE-standard networking equipment.

The IEEE 802.11b standard came out in 1999, specified a 11 Mbps signaling rate, and it’s about the oldest not totally obsolete wireless networking standard. The trouble is that IEEE 802.11b equipment appeared when DOS was almost gone from home and corporate PCs, although it still survived as a “pre-boot” environment for running Norton Ghost, Partition Magic, Drive Image, and similar products. The upshot is that until the early 2000s, there was demand for DOS networking drivers for then-current hardware.

My need was seemingly simple: I set up an old ThinkPad 760XL (166 MHz Pentium MMX) running DOS for my son to play 1990s games on, especially but not exclusively Sierra and LucasArts adventures; for that purpose, the laptop is quite suitable, it has a decent ESS sound chip and a CD-ROM. Moving data to the laptop on a CF card with a PCMCIA adapter is not difficult, but it gets old; it would be really handy to have the laptop on the network, accessing the home NAS via either SMB or NFS.

IBM ThinkPad 760XL with Cisco Aironet PCM350 WiFi PC Card.
Vintage Wireless, circa 2000

The laptop is of course old enough that it has no built-in Ethernet or WiFi, although it has two PCMCIA/CardBus (at least I believe they’re also functional as CardBus) slots. But the laptop is portable, and it’s in a corner of the house where there’s no Ethernet socket nearby. So WiFi would be really great. But is it even possible to get a DOS laptop on a WiFi network in 2019?

The short answer is “yes, but”. The long answer follows.

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Posted in DOS, Networking, Wireless | 20 Comments

More on NX Insanity

Posted on November 29, 2019 by Michal Necasek

This article was supposed to be published about two years ago but got forgotten and ignored until now. It’s not the only such article. Perhaps it will start a new “better published late than never” series.

After looking more closely into the nonsense surrounding the implementation and usage of the NX feature, I ended up with more questions than answers. And it’s definitely not the fault of AMD, the people who first defined and implemented NX.

A big contributor is Microsoft, too. The code to detect and enable NX in Windows 10 (analyzing the original 10240 build here) is, to put it mildly, weird. That is very much at odds with Server 2003 (WRK) which has completely straightforward code to detect and, if present and requested, enable NX.

First let’s consider 64-bit Windows 10 10240 because it’s simpler. Given that NX was introduced in and defined as a non-optional part of the AMD64 architecture, a 64-bit OS should be able to query bit 20 (NX) in CPUID leaf 80000001h, register EDX. But that’s not what Windows 10 does. Continue reading →

Posted in AMD, Bugs, Intel, Microsoft | 13 Comments

The Sad End of Intel Desktop Boards

Posted on November 11, 2019 by Michal Necasek

As previously discussed on this blog, Intel decided to quit the desktop board business in 2013. What has not been discussed is how Intel treated the buyers of the last generation (i.e. 8-series Lynx Point chipsets) of those boards. Since I have now acquired two of those boards, DZ87KLT-75K and DQ87PG, I had an opportunity to familiarize myself with the situation.

The DZ87KLT (Kinsley Thunderbolt) and DQ87PG (Spring Cave) were released in mid-2013 and were sold for about three years. They supported the then-new LGA1150 socket for Haswell CPUs.

In 2014, Intel released the updated and faster Haswell Refresh CPUs, as well as the Devil’s Canyon i7-4790K, Intel’s first 4.0 GHz processor (ten years after the Pentium 4 very nearly got there first). For most owners of existing LGA1150 boards, supporting the new processors was just a matter of updating the BIOS.

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Posted in Intel, PC hardware, Software Hacks | 15 Comments

The i860 Conspiracy

Posted on November 10, 2019 by Michal Necasek

I’ve been thinking of acquiring a board with the Intel 860 (Colusa) chipset. This chipset is historically interesting because it was Intel’s first chipset for NetBurst Xeons, and–at least according to Intel–the only chipset that supports the original Foster Xeon DP processors with the 180nm Willamette core.

The platform is interesting because it was Intel’s first dual-socket Pentium 4 implementation, and the i860 chipset was also the first with support for certain modern amenities like Message Signaled Interrupts (MSIs), enabled by the switch from a dedicated APIC bus to interrupt delivery via FSB messages.

The catch is that the i860 chipset was relatively short-lived, having been cursed with RDRAM. The i860 was introduced in May 2001, and in February 2002 it was already superseded by the DDR SDRAM-based E7500 (Plumas) chipset, which also coincided with the release of 130nm Prestonia Xeons based on the Northwood core.

The i860 was apparently so short-lived that Intel did not manage to release its own board based on the Colusa chipset. There were apparently only four board vendors who did: There was Supermicro P4DCE and P4DC6 (I am guessing that P4DC stands for Pentium 4 Dual Colusa); there was Tyan Thunder i860 (S2603); there was MSI 860D Pro; and there was an obscure Iwill DX400-SN.

The MSI and Iwill boards appear to be very hard to find. The Supermicro and Tyan boards are not, but there’s a catch.

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Posted in Intel, PC hardware, PC history | 15 Comments

More About That Strange Pentium 4

Posted on October 26, 2019 by Michal Necasek

A few years ago I wrote about a strange NetBurst processor with SL7HY S-spec that landed at the OS/2 Museum. After renewed reader interest I pulled it out of the closet and tested the processor again. A collection of miscellaneous notes follows.

CPU-Z today is just as clueless as it was a few years ago (no surprise), thinking it’s a Socket 604 processor and that it’s an engineering sample:

CPU-Z misidentifying the SL7HY processor

The SL7HY processor was briefly tested in an ASUS P5PE-VM board. The BIOS complains at boot-up that it has no microcode for the processor, and clearly shows the brand string as Intel(R) Xeon(TM) CPU 3.73GHz. That gives me confidence that this product string is really what’s burned into the processor.

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Posted in Intel, PC hardware, PC history, Pentium 4, Undocumented | 32 Comments

It’s Zen Time

Posted on October 14, 2019 by Michal Necasek

Back in 2003, it was Hammer Time for the PC industry. My own home PCs missed the wave because I had just bought a 3.2 GHz Northwood Pentium 4, which was replaced in 2006 by a Core 2 E6600, a 64-bit dual-core Intel CPU running at 2.4 GHz. The Core 2 was not really better than Athlon 64s and Phenoms, but it wasn’t worse either. And when the next upgrade came in 2011, Intel’s Core i7 unfortunately did not have much real competition from AMD.

But that was when Intel still made desktop boards (I’ve been overall very happy with the DQ67OW board), and years before AMD processors were reborn with the Zen microarchitecture. Part of the reason why I stuck with Intel is that I’d had bad experience with boards and chipsets for AMD CPUs, but AMD eventually saw the light and realized that it’s not helpful to their cause to rely on the likes of VIA or nForce.

After a very useful discussion on a previous blog post, I decided to go for the ASRock X570 Pro4 board. That was about the only board I could find which combines the lack of silly bling and things I really don’t need (like onboard WiFi) with an Intel Ethernet controller, since I’m happy to spend extra money to avoid Realtek Ethernet chips.

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Posted in AMD, PC hardware, Ryzen | 8 Comments

Synology Strikes Again

Posted on October 10, 2019 by Michal Necasek

Three years ago I ran into a problem with a Synology DSM update preventing vintage SMB clients from connecting to my NAS. Now I ran into a similar but different problem.

The symptom was DOS and (at least old) OS/2 clients refusing to connect to my NAS, like this:

C:\>net view \\mynas
Error 58: The network has responded incorrectly

C:\>dir n:\
Incorrect response from network
Abort, Retry, Fail?

I had updated DSM not long ago, but I suspected that that hadn’t been the trigger. More likely this happened because I got tired of fresh Windows 10 installs complaining that they don’t want to talk to SMB1, and changed the DSM settings to support everything from SMB1 to SMB3. But DOS uses SMB1, right? Well…

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Posted in LAN Manager, Networking, Software Hacks | Leave a comment

PC Keyboard: The First Five Years

Posted on September 3, 2019 by Michal Necasek

The vast majority of PC users today have no memory of what PC keyboards looked like before the standard 101/102-key layout arrived, even though various OEMs do their best to mangle the standard layout in order to minimize usability, especially on laptops. OEM-specific modifications aside, the basic layout of the main block of alphanumeric keys has not changed in over 30 years, since 1986.

However, up until that point the PC keyboard layout and the keyboard hardware changed quite a bit, and looking at the 1981-1986 IBM Technical References is key to understanding a) why the standard keyboard scan codes are so complex, and b) why there are so many seemingly odd vendor-specific modifications of the standard layout.

83-key Layout, 1981

All keyboard diagrams were borrowed from IBM Technical References. The original PC keyboard (1981) looked like this:

Original 83-key PC keyboard, 1981

From today’s perspective, that keyboard looks rather strange for a number of reasons.

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Posted in IBM, Keyboard, PC hardware, PC history | 19 Comments

How Not to Buy a Computer

Posted on August 24, 2019 by Michal Necasek

The following is an unauthorized translation of an article by Jiří Franěk, published in the Czechoslovak computer magazine List sometime in early 1989. Some readers probably remember those times, others have forgotten. As for the rest—consider yourselves lucky.

The number of computers in our households keeps going up, despite domestic production contributing extremely little—and foreign trade only very slightly more—toward that end. Individual import from abroad is still the most “natural” way of obtaining a computer and peripherals. But the process is not without pitfalls.

One of the proven methods of not buying a computer (or even better a printer) is a purchase through a third party. “Dear auntie, I have a pressing need to buy a Seikosha GP 100 printer and Multiface II for my ZX Spectrum1. Both are very cheap and in Munich you can probably find them in every drug store.” Auntie will waste a lot of time shopping but never find the desired peripherals even in the most specialized store. Those who have spent some time abroad (and know how the foreign markets work) no doubt understand the problem. For the rest, unfortunately the majority, an explanation follows.

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Posted in PC history, PC press | 27 Comments