You want the type of scaling that this laptop and your Siemens Nixdorf does - the fullscreen scale breaks the aspect ratio. That’s what causes games like Keen 4 to glitch and text to get all messed up. DOS games weren’t even designed for 4:3, they’re 320x200/640x400. The most accurate scaling is that which preserves the aspect ratio so nothing gets stretched out of proportion.
If you just prefer to play fullscreen with the messy text, then that’s fine, but is not accurate scaling.
320x200 may well not be 4:3 pixel aspect ratio, but it was definitely displayed in that aspect ratio on all of the millions of VGA monitors that DOS ran on in the 80's/90's.
I'd argue that playing those games with purely integer scaling on a laptop LCD (with the resulting top/bottom borders) does not replicate the same aspect ratio that we had on CRT monitors.
Whether the vertically squashed linear-scale output, or the scaled-up (possibly pixellated; depending on scaling capability of the video chip) output is more preferable is going to be entirely down to user choice. But I think it is wrong to claim one or the other is 'most accurate'. Neither accurately reflect what those games looked like on a native CRT.
I see what you're saying, but it's a little more complicated then that. Yes, vertical scaling generally looks and works fine, which is why my absolute perfect DOS laptop is one that has a 640x480 LCD and does a vertical scale, meaning it fills the entire screen, versus some 640x480 laptops that will display DOS games as 640x400. However, since 800x600 and 1024x768 screens can't do a perfect 1:1 scale from 640x400/480 or 320x200/240, it messes with the graphics in an unintended and negative way. That's also what causes certain games like Keen 4 to have visual glitches.
Here's a few photos of the Keen text to serve as an example.
These first two were taken of my Alpha-Top Green751, which is a Pentium 75 laptop with a TFT 640x480 LCD and C&T 65545 graphics. This laptop is my current go-to for DOS games because it's a good machine, and because I can use a keyboard function key to switch between "native" scaling (320x200 -> 640x400) or vertically stretched scaling (320x200 -> 640x480). Not many laptops will let you pick between the two.
First image is in native scaling, second is with vertical scaling. Both look good.
This third image was taken of my CTX EzBook 700, which has the NeoMagic NM2093 graphics (MagicGraph 128ZV). This laptop always scales to fullscreen with no key or BIOS option to switch to black border mode. Since it's an 800x600 LCD, it does the typical bad fractional scaling to fill the whole screen, that as you can see looks awful. NeoMagic chipsets were the worst of them all in this regard, but the Cirrus and C&T chips were hardly better and still have scrolling glitches in Keen.
Finally is the Brother Meritus A53 (1024x768 LCD) which scales up the 320x200 natively to a "big enough" image that still leaves some borders, but far less than leaving it un-scaled. For whatever reason, text looks the same as on the NeoMagic despite it not doing a fullscreen scale. That being said, it's still better than the typical fullscreen scaling because it doesn't cause any bugs in Keen or any other game that would be affected on an earlier laptop.
The best panel option for scaling 320x200 content would actually be a 1280x1024 screen, as it offers the closest-to-integer scaling in both X and Y dimensions for that mode:
This is if we only accept basic integer scaling algorithms from C&T, Cirrus, Neomagic, early S3 and ATI mobile chips. Once you start getting in to chips which offer better options like bilinear filtering and automatic interpolation of non-native screen modes then things become a lot less clear, and having the highest resolution panel would probably be the best option in that case.
Unfortunately most of that tech started to come in at the very tail end of models with any meaningful native-DOS sound support.
Once again, as we've seen over the 40+ pages of this thread, there isn't a one-size-fits-all golden solution! 🙁 For me, that solution would be something similar to the dimensions of my Thinkpad 240 or 240X, but with a proper ISA soundcard instead of PCI and perhaps a slightly beefier video chip that still had Fn+hotkey full screen scaling options.... but there isn't such a thing, as far as I'm aware (I've got >150 laptops in a spreadsheet here sourced from all the discussions had so far, and they *all* have compromises....)
If you're looking at a laptop from the late 90s and on, then yes, definitely, there is no perfect solution. You can get real close with that 1994-1995 era where you had 640x480 LCDs and sound cards, but the compromise there is that those laptops don't have wavetable/midi support. If you don't care about that, then you can get a no-compromise laptop that does great soundblaster and adlib sound. I've got my WinBook XP5 which is still riddled with some electrical gremlins, and then the Alpha-Top Green751 I referenced earlier which is nearly as good and actually works properly. Of course the issue here is that such laptops are hard to find and are generally unreliable.
I think the late 90s laptops like my Brother laptop are a good compromise though. Plenty out there that do the same type of scaling that aren't as rare as my example is, you can definitely find *a* laptop that's good enough in this regard.
No perfect option though, that simply doesn't exist.
Owner of https://www.macdat.net, the largest vintage laptop documentation resource on the web!
Hot tip: if you disable MPU401 in essolo.ini, then it (apparently) also locks up/disables the keyboard on the TP240. I had to shuffle the Solo-1E MPU401 port to a different address (0x300 in my case), rather than disabling it, to use the Roland PCMCIA card.
It's now mostly working as I want it to, including mixing the Roland stereo output into the onboard line-in (yes, it's only playing via a mono onboard speaker - but you can use headphones to bypass that). For me the size of this thing is absolutely the killer feature.
Benchmarks for the Thinkpad 240 (Mobile Celeron 300), using several slowdown tools.
- The IBM 'PS2' tool has a 'SPEED' parameter which you can use to set the following values:
--- FIXEDMAX; the default 300MHz
--- FIXEDMEDIUM; 225MHz
--- FIXEDSLOW; 150MHz
--- FIXEDMIN; this seems bugged and gives results closest to FIXEDMEDIUM
--- Plus some others that are more for mobile use (i.e. not really for setting a specific speed)
- Setmul works to enable and disable L1 and L2 cache; which CPUSPD cannot do itself.
- CPUSPD works to set frequency duty, from a state of T1 (lowest duty) to T8 (highest, and default clock) - that's all it can do with the P2/Celeron and this chipset, but that by itself is pretty extensive, as we will see.
Using just the PS2 SPEED parameter and SETMUL gets some decent slowdowns, but it's very spiky and with some odd performance drop-offs, more than might be expected:
Values other than T8 or T7 in CPUSPD don't seem to work if you have set "PS2 SPEED FIXEDMAX". This seems to make the system reset to the highest duty state (T8) shortly after issuing the CPUSPD command. Fortunately if you want to use a state lower than T7, issuing a "PS2 SPEED FIXEDMEDIUM" and then the required CPUSPD command appears to make the lower duty levels work correctly.
This gives a rough spread of equivalent machines to include most of the more popular PC gaming eras, including the ubiquitous DX2-66, low-end 486 and high-end 386. It can also just about do the equivalent of a top end 286; matching the scores of some of my better performing 20MHz boards:
I find myself pondering a very far off perfect Epson ActionNote 4slc/33, which is on the radar locally. Mono LCD, VGA only, no S, and of course the CPU doesn't exactly punch in the real 486 weight class. It is available and affordable though, and seems only to need a new HDD. I am thinking of it as "replacing" my z-lite 320 and z-star 433 which have numerous electronic problems, but worse, have plastics that have rotted to chocolate or cheeselike consistency, so while the electronics might be repaired, they might end up mounted to a literal breadboard for mechanical stability, and only used desktop style with kb/mon. So while I have a fondness for the plodding greyscales of those, nostalgia based since I owned the 320 from 1995, they are trending rapidly away from being able to be used in any manner similar to a laptop. Thus I find an ActionNote, which probably splits the performance difference between them, since the zstar has a slc2, somewhat attractive for it's apparent ability to maintain it's shape at least. Around the retro world, a couple of owners seem to be charmed by them, liking the crispness of the LCD, even if it has all the normal drawbacks, liking the keyboard, liking the size. Also quite appealing is the 2 serial ports. No PCMCIA to be had though. It has also been shown that an 8xAA battery holder fits in the battery compartment and can be populated with regular NiMh AAs.
Anyway, considering going for it, for ~'88 to '92 DOSing around, in whatever I can bear without color and with blur, and no sound apart from maybe speaker or if I make it a covox. Though actually, I find I really only play fast action games much on desktop anyway, need to sit up and focus, rather than slouch and chill.
Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.
C&T CT65548 1MB Local Bus video (not so friendly with Duke3D as it states the card is not compatible,
I found a Tecra 700CT in a garage with the same chipset. Out of curiousity I tested Duke3d and it ran just fine. That being said I'm probably going to toss it in the bin. If I get the time I might go through it well and remove the batteries so they dont leak before that.
They really are lovely looking machines, and the scaling from the ATI Mobility chip is light years ahead of the old S3, Neomagic and C&T chips. The 1400x1050 screen on the 809K in particular is very, very nice indeed.
But.
They all suffer from leaking CMOS (possibly just RTC) batteries at the front of the machine. *AND* the entire PCG-Fxxx series has a flaw in the power control board (one: it is right next to the leaky battery, and two: they seem to just fail randomly without any visible indicators).
I've been through three different power control boards (and two different laptops - an entire machine bought for spares); eventually finding one working one, but it only lasted 2 days before it also failed.
As a result, I really cannot reccomend anyone buy an old Vaio PCG-Fxxx model - it *will* fail at some point.
Currently have a bid on an older Compaq Armada 1750 - a bit of a chunkier P2 based machine, with older ATI Rage LT graphics (from the point that ATI introduced their nice 'ratiometric' scaling), but still with nice ESS Audiodrive sound.
megatron-ukwrote on 2024-12-30, 20:44:- The IBM 'PS2' tool has a 'SPEED' parameter which you can use to set the following values:
--- FIXEDMAX; the default 300MHz
--- […] Show full quote
- The IBM 'PS2' tool has a 'SPEED' parameter which you can use to set the following values:
--- FIXEDMAX; the default 300MHz
--- FIXEDMEDIUM; 225MHz
--- FIXEDSLOW; 150MHz
--- FIXEDMIN; this seems bugged and gives results closest to FIXEDMEDIUM
--- Plus some others that are more for mobile use (i.e. not really for setting a specific speed)
Do you have a link for that tool? It's impossible to search for, for obvious stupid-name reasons.
My cheap Compaq Armada 1750 arrived today. As expected it was not devoid of issues, but on the whole I am pleased with the condition. As advertised; quite grubby:
Today, after a little clean up with a magic eraser, soap and water, just a few minor blemishes on the top case (looks worse in photo than it actually is):
- P2 333
- 128MB (64MB + 64MB)
- ATI Rage LT Pro 4MB
- ESS Audiodrive 1869
- 14" 1024x768 screen
- CD
- 6GB HDD
- No modem/ethernet
Good points are that it all works, including the drive (which has a working install of XP SP2 on), the FDD and CD work. Screen is clear and free of any blemishes/dead pixels, sound/speakers works.
Bad points; no main battery module, the CMOS battery is flat and the bezel around the screen was loose (cracked retaining clips) on the left edge of the screen.
I've already glued the screen bezel and just need to figure out the easiest way of replacing the CMOS battery (a 2032, by the looks of it). I'd also like to get a battery for it.
One thing I have read up on these machines is that they can take faster MMC-2 modules.... and I happen to have a Pentium 3 650 MMC-2, that I bought new for peanuts about 15 years ago. I understand that you lose the speedstep ability, and that they constantly run at the lower frequency (i.e. -150MHz under rated speed; hence 500MHz for my 650 module)... but that since the chipset is on the MMC-2... everything then gets boosted up from the (current) 66MHz bus the 1750 uses at standard.
The other job I have is to replace the internal HDD with an mSATA drive... but I believe I need to do something with a Compaq soft bios boot floppy or similar to do this (some bios data is held on the drive, ISTR?).
P3-650/100 Speedstep module is now installed. Running at 500MHz/100MHz. The original module is a P2-333/66MHz.
While I was at it I pulled out the original 64MB Compaq upgrade SODIMM and replaced it with a 128MB part instead, for a total of 192MB. I did try a 256MB module but it didn't like it - probably too high density (that's officially an unsupported config anyway); if I come across a low density 256MB SODIMM I may try it, but I'm not going to buy one specifically. The onboard memory appears to be happy running at 100MHz.
I haven't re-enabled the L2 cache yet, but that should be easy enough to do via SETMUL, CPUSPD or similar. Even without that it booted into XP way quicker.
Next is to replace the internal 2.5" HDD with the mSATA drive - I'll need to hunt down the Compaq setup floppy image first.
What is it with me? I really don't seem to be having much luck at the moment!....
Had the Armada on, sitting at the XP desktop while I am downloading the Compaq diagnostic floppy and bios floppy images... I'm writing them to floppy on my other PC and then all of a sudden the Armada blue screens, reboots and sits with the LCD off and all of the led keyboard indicators lit.
Power cycling does nothing. Swapping back to the P2 CPU module doesn't change it. It barely felt warm around the CPU/fan area. Leaving the HDD out and just the onboard ram, nope.
My last laptop purchases lasted 2 days of runtime. This one didn't even get 2 hours on it 🤣😂
I just took a gamble on another pair of Sony Vaio laptops. This time a PCG-Z600RE and PCG-Z600TE - UK/Euro versions of the PCG-Z505HS and PCG-Z505LS.
One has a 2.5MB NeoMagic 256AV vga and a 500MHz PIII, the other has 8MB ATI Rage Mobility M1 and 700MHz PIII. Both have Yamaha YM744B/DS-1/XG audio. Both have a very nice magnesium alloy case - it's really quite sturdy. They also don't have a suicide power control board or leaky NiCd/NiMh, from what I can see (so far).
Sadly I've only been able to put together one working machine from the two (of course I chose the ATI-equipped model!) - with a combination of torn ffc cables from the keyboard and track pad, missing hard drive ffc and only one keyboard. They were cheap for the pair though.
On closer inspection, and from the BIOS menu, it turns out that what I thought was the Z600TEK is actually a Z600HEK; the difference being a PIII-800 in the HEK, in place of the 700MHz model in the TEK. So that's a result, I guess.
It only had the base 128MB ram fitted, so I swapped in a 256MB SODIMM, and it's registered all 384MB, which is nice. I also dropped in the 128GB mSATA drive from the last Vaio I tried (PCG-F807K). Boots fine, and speedsys confirms it seems to be working as expected. It's doing the nice, non-integer, interpolated upscaling that RAGE LT and later chips do, which is why I wanted it.
The case needs a bit of tidying up, and it was missing every-single-damn-screw! Also a few plastic trim pieces (mainly around the USB port on the right).
It will need putting through it's paces of course... and as yet I don't know if the battery charges/holds a charge.
