First post, by jheronimus
I've completed my second build, the 486dx2 Compaq Presario 433. And it's a beauty!
According to the label on the back of the monitor this machine was released in May 1994. It's largely similar to the first Compaq all-in-one, the Presario 425, and was succeeded by Presario CDS/CDTV series. Additionally, similar machines with an integrated NIC were available under the Prolinea brand (Net 1/25s, Net 1/33s, etc).
The machine came in pretty empty: it had the original FDD and a 425,3 MB Western Digital Caviar 2420 HDD. The motherboard has 4 MB RAM soldered on and an integrated Cirrus Logic CL-GD5420 512K videochip.
All the electronic parts were working perfectly, but the mechanical parts did not age well. The power-on button works 50% of the time, and the plastic backplate of the motherboard cage broke off when I tried to eject the cage.
My plan was to get a 486DX2 CPU, upgrade the HDD to the Quantum Fireball 2.5a (2,5 GB), add some spare SIMMs I had from my Pentium build and use something from my heap of Vibra 16/AWE64 and ESS soundcards. It took me less than one day to get this machine to work the way I wanted, which is a huge step-up from 2-3 weeks I spent on my Socket 7 build. Having a lot of spare parts certainly helped. There were, however, some bad surprises.
First, the BIOS. Presario machines are said to have a proprietary GUI BIOS that must be installed to the hard drive. This is only partly true. Yes, if you really want a GUI, you need the recovery disks, those can be found here — they are universal for 425/433 and the CDS series. However, the system actually has a pseudo-GUI BIOS in ROM that has largely the same functionality. Anyways, I couldn't install the graphical BIOS to the disk, so I skipped this part.
Second, the HDD. My 2,5 gig Quantum Fireball was not detected by the BIOS or by the MS-DOS setup disk. I tried different HDD jumper settings, also tried telling the BIOS this is a 615 MB disk, but it just can't see it, and I don't know why. So I had to stick with the WD disk it came with. Scandisk says there are no bad blocks, but I realise that with a 22 years old HDD the system is bound to fail some time soon.
It says here that the disk controller is "WDC Compatible", could that possibly mean that it only accepts Wester Digital disks of a certain standard? I don't know. The guy used a "a laptop disk with an adapter", so I guess it should not have any restrictions. Could it be that the 2.5a disk was FAT32 (it has Windows 98SE installed) and DOS 6.22 doesn't support it?
Third, the RAM. The limit for this system is 20 MB. It didn't like my EDO sticks at all, so I had to stick with FPM modules. However, I could only use additional 8 MB (for a total of 12). Every time I tried adding another 8 MB resulted in the system entering an endless boot loop. Well, 12 MB should still be enough for a 486 machine, right? 😀
Fourth, the sound. This machine has two ISA slots and for some reason the ESS had to be installed into the first one. I only have ISA soundcards, so I can't tell whether it's due to a faulty ISA slot or not.
After all, here are my final specs:
14 inch 1024 x 768 CRT screen;
Intel 486dx2-66 CPU;
12 MB RAM;
425,3 MB HDD;
ESS AudioDrive ES1868F sound card;
Cirrus Logic CL-GD5420 512K.
P.S.: for some reason, the motherboard has a second power connector. It doesn't have a second IDE, so I don't know what it was supposed to be powering. Maybe I'll use it for a CPU cooler if my Socket 7 cooler fits on a 486dx2. Right now it uses a radiator.
My first ever machine was my father's 486 Toshiba Satellite laptop running Windows 95 and my relatives' Windows 98 Pentium box, so I never actually used a pure DOS. However, seeing as how I don't have a lot of disk space, and this machine won't be used for any Windows games or software, using anything but MS-DOS seemed like a waste. As such, I installed MS-DOS 6.22 (with the additional tools from the 4th disk!) and Norton Commander 5.51.
I have to say, configuring MS-DOS seems A LOT simpler than a Windows 9x box. A lot of hardware does not require drivers or configuration at all. Even when some hardware does require additional software, it doesn't look for some unique version. I mean, all Compaq bundled software is compatible with all Presario 486 all-in-ones! Compare that to Creative soundcards each requiring different drivers and software under Win9x. So, after all, I did not have to do anything to get my videocard or my joystick to work. Configuring ESS was also a matter of installing some software (that is universal for all ESS cards) and modifying autoexec.bat).
I also got the CPQDOS bundle. The most important tool here is the MODE utility that is a software equivalent of a TURBO button. It can disable memcache and change CPU speed. The problem is that possible settings are: auto, common, high and fast. Which of those would be similar to 386? The docs don't explain that at all 😀
I also got some tips from here. The stock DOS prompt is atrocious if you ever used a Linux/OS X shell, so enhanced DOSKEY is a life-saver.
I used this article to configure my ESS AudioDrive. Have to say, even after setting everything to 15, it's still pretty quiet. I don't remember where I got the tools, so just google for "ESS_DOS_config.zip".
Have to say, if setting up DOS was almost a walk in the park, getting the actual games to work is a nightmare — again, since I don't have any DOS gaming experience.
- Lands of Lore crashes after the character selection screen. I guess it's because the CPU is too fast, but I can't figure out the proper settings.
- DOOM 2 starts 25% of the time — it mostly just gives me a division by zero error. Even if I do manage to get to the main menu, the game waits a bit and then the screen quadruples and everything freezes.
- Wing Commander works pretty nicely with the Compaq mode utility.
- X-COM UFO Defense also runs well.
Any tips here?
Also I had a major disappointment with joystick support. Looks like most early 90s games like Wing Commander 1 and LHX don't utilise anything besides the stick and two buttons. So my Quickshot QS-201 is an overkill: its two extra buttons and throttle control don't work. Maybe my programmable Gravis Phoenix will work better though.
I'm more or less happy with the specs now. It would be nice to replace the HDD, but it's not crucial. The biggest issue is data transfer. I'm just using my Socket 7 machine to flash IMG files on floppy drives, and it's annoying as hell.
I see the following options:
- LPT IDE CD-ROM. Pros: can play CD games, like Lucas Arts quests. Cons: messy (requires external power) and slow. Also, I can't find any offers in the Russian internet.
- ISA NIC. Pros: convenient. Cons: Hard to configure. Also, AFAIK, NICs use a lot of resources my DOS standards. Also not sure it would be too fast. Even my Pentium's 100 MB NIC is pretty slow.
- Insert a mobile rack into my Socket 7 machine. Right now it seems to be the cheapest and simplest option, thanks to Compaq design. Whenever I need to transfer a bunch of games or software, just take the disk out of Presario (it doesn't really need to be screwed to anything, and the cage is easy to eject) and write stuff directly to it. Use floppies for anything smaller than that (still amazed by how many DOS apps can fit onto a single 1,44 MB disk).
BTW, is there anything like a virtual drive for MS DOS? Is there a way to mount IMG/ISO files?
All in all, I'm pretty happy with this machine. I was lucky that all of its parts work perfectly well and it's pretty fun. Getting games to run will take some time to get used to, but this is why I wanted to do this in the first place, right?