Alesia wrote on 2026-08-01, 05:02:

Not retro per-say, but I realised there wasn't really a solution to use coin cell batteries in place of a 4.5v battery brick ala Rayovac 840 ect. So I went around with what little pcb/electronics knowledge I have and whipped something up. I know it's not "proper" by using an SMD LDO but I couldn't find one that was what I needed in any of the Kicad libraries I have setup and SMD stuff would kind of make it hard to assemble so I just went with diodes. I also assembled several normal 4.5v battery packs in the meantime because I was super tired of having to punch in 10 different values every time I turned my Zeos 486 on 🤣. Still need to learn blender so I can make a 3d printed case to hold everything, but I'm hoping to get some prototypes in hand so I can see if I misread how I was supposed to do things electrically.

The attachment Screenshot from 2026-07-31 21-50-08.png is no longer available

Which LDO did you want to consider? I suspect you're taking 6V from the coin-cells and want to go down to 4.5V as needed by the system?

tehsiggi wrote on 2026-08-01, 07:05:

Alesia wrote on 2026-08-01, 05:02:

Not retro per-say, but I realised there wasn't really a solution to use coin cell batteries in place of a 4.5v battery brick ala Rayovac 840 ect. So I went around with what little pcb/electronics knowledge I have and whipped something up. I know it's not "proper" by using an SMD LDO but I couldn't find one that was what I needed in any of the Kicad libraries I have setup and SMD stuff would kind of make it hard to assemble so I just went with diodes. I also assembled several normal 4.5v battery packs in the meantime because I was super tired of having to punch in 10 different values every time I turned my Zeos 486 on 🤣. Still need to learn blender so I can make a 3d printed case to hold everything, but I'm hoping to get some prototypes in hand so I can see if I misread how I was supposed to do things electrically.

The attachment Screenshot from 2026-07-31 21-50-08.png is no longer available

Which LDO did you want to consider? I suspect you're taking 6V from the coin-cells and want to go down to 4.5V as needed by the system?

A friend recommended the XC6702D451PR-G which is a 4.5v output LDO but all the SOT-89-5 package footprints/whatever I have in kicad have different pinouts to it became very difficult to ensure my traces were connected to the right pads because I was essentially wiring for the "wrong" thing using another as a stand-in. So I finished up the "dumb" 6v - .7v -.7v = 4.5v diode version because it was just easier to do short term and easier to assemble. My confidence with all this is very low, I'm just trying to solve some low hanging fruit problems for the community and owners of things like my Zeos 486 that only support these off-board battery brick type 4.5v things for CMOS power. Especially just avoiding AA batteries in general because of leakage.

Planning to re-attempt my powerbook 150 battery board soon too, but I have to block the charge current and work within some extreme space constraints, plus give up on my dream of using a rechargeable battery for it because non of the types in current production are usable (too big, ironically.) So I have a lot to learn.

Hello everybody

I don't know, whether we are allowed to complain against some professional eBay hardware sellers?
If so, I d like to warn everyone here, not to buy stuff from derOptimus.de!

Why?

This is the 2nd mainboard, which I have bought, and which is not working:

1. 3 months ago I bought an ECS P5HX-B and after installing it, it even didn't start
=> fortunately I was allowed to send it back and received my money via PayPal.
2. now I have tried to install the recently bought ATrend ATC-5130 S7 Board.
=> I have discovered that a part of the socket is broken:

https://www.ebay.de/itm/404685091488

Look at the picture below plz.
I m very disappointed.

In general this is a marvelous board, as it has:
1. multiplier till 3.5x
2. FSB 60,66,75,83Mhz
3. SDRAM support along with EDO RAM
4. 2.0Volt to 3.5Volt
5. Beta Bios supporting K6-2 400
6. 512KB 2nd level Cache
7. Socket for additional 11-Bit TAG-SRAM module in order to cache up to 512MB RAM
8. ALI4+ Chipset
9. USB 1.1 and PS/2 connectivity
10. CR2032 Battery instead of the old RTC Dallas

I m really angry!
Now I will go out and drink some beer to cool down.

I bought the Asus A7N8X from there; the first time he delivered 1.04 and the second time he delivered 2.0 as stated in the original. But the BIOS is corrupted...

30K transactions predominantly positive, sounds like you got unlucky or they god lazy checking what they are selling.

I got a Socket 7 board: Asus P5A-B Rev 1.04. Are all the I/O ports standard on that board?

RetroLizard wrote on 2026-08-03, 03:30:

I got a Socket 7 board: Asus P5A-B Rev 1.04. Are all the I/O ports standard on that board?

Socket 7 eh? That's a platform I have zero experience with and need to get my hands on one day, whether it's the original version or the later Super Socket 7. Oldest desktop hardware I've really played around with is OEM Slot 1 stuff, currently have a Dell Precision 410 that has a single Pentium II 350 but can do dual CPU's - and for laptops, the oldest I've had any interest in playing around with is my Dell Latitude XPi CD M166ST with a 166MHz PMMX.

Since S7 is from the AT-ATX transitional era, I can't really answer the part of if any of the ports are standardized.

versawizkid2002 wrote on 2026-08-04, 02:32:

RetroLizard wrote on 2026-08-03, 03:30:

I got a Socket 7 board: Asus P5A-B Rev 1.04. Are all the I/O ports standard on that board?

Socket 7 eh? That's a platform I have zero experience with and need to get my hands on one day, whether it's the original version or the later Super Socket 7. Oldest desktop hardware I've really played around with is OEM Slot 1 stuff, currently have a Dell Precision 410 that has a single Pentium II 350 but can do dual CPU's - and for laptops, the oldest I've had any interest in playing around with is my Dell Latitude XPi CD M166ST with a 166MHz PMMX.

Since S7 is from the AT-ATX transitional era, I can't really answer the part of if any of the ports are standardized.

Dell Latitude XPi CD M166ST with a 166MHz PMMX sounds like a Socket 7-based laptop. Obviously not in the same way as a desktop machine, but it's got a lot of the same hardware.

RetroLizard wrote on 2026-08-04, 02:35:

versawizkid2002 wrote on 2026-08-04, 02:32:

RetroLizard wrote on 2026-08-03, 03:30:

I got a Socket 7 board: Asus P5A-B Rev 1.04. Are all the I/O ports standard on that board?

Socket 7 eh? That's a platform I have zero experience with and need to get my hands on one day, whether it's the original version or the later Super Socket 7. Oldest desktop hardware I've really played around with is OEM Slot 1 stuff, currently have a Dell Precision 410 that has a single Pentium II 350 but can do dual CPU's - and for laptops, the oldest I've had any interest in playing around with is my Dell Latitude XPi CD M166ST with a 166MHz PMMX.

Since S7 is from the AT-ATX transitional era, I can't really answer the part of if any of the ports are standardized.

Dell Latitude XPi CD M166ST with a 166MHz PMMX sounds like a Socket 7-based laptop. Obviously not in the same way as a desktop machine, but it's got a lot of the same hardware.

You technically would be correct, though I think the XPi CD uses a soldered TCP (tape carrier package). Still very much like Socket 7 at heart though, and it is a P55LM core chip so it's 350nm just like what you'd find on a desktop P55C-based PMMX.

rasz_pl wrote on 2026-08-03, 02:45:

30K transactions predominantly positive, sounds like you got unlucky or they god lazy checking what they are selling.

Fortunately I received back my money: 35€
Thx to eBay customer service

Asus P5A-B has been delivered. Some of the caps don't look so great. A couple of the SD-RAM slots, as well as the ATX connector, appear to be slightly crooked.

Other than those problems, the board appears to be in fine condition. I'm just waiting on a 366Mhz CPU and replacement caps to arrive before I test it out.

Learned a few things about FAT12:

• Windows doesn't tell FAT12 or FAT16 apart under Properties; requires chkdsk (shows clusters) or directly after formatting (shows 12-bit or 16-bit).
• FAT12 has less than 2^12 clusters (usually less than 4K); FAT16 has less than 2^16 clusters (usually around 60K).
• Memory cards with 16MB or less are formatted with FAT12; cards with 32MB or more (up to 2GB) are formatted with FAT16.

Everything started with someone asking for help on RedNote as her 1997-vintage Epson Colorio CP-500 (also known as "PhotoPC 600" in Europe and North America) couldn't recognize an 128MB CF card. A card with just 128MB was already quite small in capacity...... or was it?

Dug up a review article in Japanese:

しかし、20MB以上のカードはFATの構造が異なり、現時点では「CP-500」は対応できず、事実上は15MBカードまでとなる

I knew floppy disks were all in FAT12 but I didn't know its upper limit. Took several of my low capacity memory cards (8-128MB) and re-formatted them; only those with 16MB or less (I didin't have any 24MB card) would be formatted as FAT12.

dormcat wrote on Yesterday, 02:26:

Learned a few things about FAT12: ...

You might be interested in FDI (Floppy Disk Image) which is a little tool I wrote to "do things" on FAT12 .IMGs of floppies without having to write them to a disk and back.
a .IMG being a raw sector dump of the floppy.

-Create .IMG (any of the common sizes)
- List directory contained in image
- Read file(s) from the image
- Write file(S) to the image
- "Clean" the image (eliminate deleted data, clean up file allocation)

Back in the day I created "MDCFS" (Minimal Dos Compatible File System) mainly to allow various embedded systems to create/use diskettes that were directly compatible with DOS.
Much more recently as I've "virtualized" much of my true DOS work - I made it into a tool I could use outside of the emulators,

The source code is available in the source section of my site! (in Micro-C)

DaveDDS wrote on Yesterday, 04:02:

You might be interested in FDI (Floppy Disk Image) which is a little tool I wrote to "do things" on FAT12 .IMGs of floppies with […]
Show full quote

dormcat wrote on Yesterday, 02:26:

Learned a few things about FAT12: ...

You might be interested in FDI (Floppy Disk Image) which is a little tool I wrote to "do things" on FAT12 .IMGs of floppies without having to write them to a disk and back.
a .IMG being a raw sector dump of the floppy.

-Create .IMG (any of the common sizes)
- List directory contained in image
- Read file(s) from the image
- Write file(S) to the image
- "Clean" the image (eliminate deleted data, clean up file allocation)

Back in the day I created "MDCFS" (Minimal Dos Compatible File System) mainly to allow various embedded systems to create/use diskettes that were directly compatible with DOS.
Much more recently as I've "virtualized" much of my true DOS work - I made it into a tool I could use outside of the emulators,

The source code is available in the source section of my site! (in Micro-C)

Interesting, thanks Dave, so you can build a floppy image from scratch with that? Make a blank image, copy files to it, then use it on an emulator, a gotech floppy emulator, or write it out to physical disk? .. .. I think to achieve that back in the day I had to use about 3 different utils in "off label" mode, i.e. features they had but weren't main focus, so it was a bit of a faff.

BitWrangler wrote on Yesterday, 13:51:

Interesting, thanks Dave, so you can build a floppy image from scratch with that? Make a blank image, copy files to it, then use it on an emulator, a gotech floppy emulator, or write it out to physical disk?

Yes to all of the above.

The only caveat is that FDI.COM is a DOS program, so to use it on a "modern" system, you have to be in DosBox (where I usually am when preparing DOS stuff 😀 )

If you just want the executable, FDI.COM is in DOSBOOT.ZIP on my site.

Btw, my XDISK.COM can write/read those (or any .IMGs) to/from "real" floppy disks (I think it's in the same .ZIP)

Under Winblow I use DSKWRITE.EXE

Fwiw, this is the "help" output if you don't give in an imagefile, which pretty much sez it all:

1FloppyDiskImage
2
3use:    FDI     [options] imagefile[.IMG] command [filespec...]
4
5opts:   y/m/d       set Date of -W files    {leave element(s)}      [from file]
6        h:m:s       set Time of -W files    {  blank for NOW }      [from file]
7        -Q          Quiet   (less output)
8        -S          Summary (list)
9        -C          no Comma in numbers
10        -N          no stop on Non-critical
11cmds:   -Bsize      BuildBlank(160,180,200,320,360,400,720,1200,1440,2880)k
12        -B0         clean existing image: eliminate deleted data!
13        -D          Delete file(s) in image
14        -R          Retrieve file(s) from image
15        -W          Write file(s) to image
16        none        list file(s) in image
17
18Does the above on "floppy disk" images:
19  simple binary files containing raw sector data, exactly as actual disk!
20which :     Used with virtual machine: VirtualBox, VMWARE, 86box, DosBox ...
21can be:     Written to real disks with: ImageDisk, XDISK, DSKWRITE ...
22
23Dave Dunfield 2026/7/14 https://dunfield.themindfactory.com

Recapped my Apple //c which is now working, not sure if I'll hang onto it since I have no nostalgia or anything for it but it is nice to see it running and doing things. Several of the small and medium caps in the internal power supply were pushing their plugs out of their bottoms so things had gone off for sure. The main big axial cap in that power supply also weighs a fraction the smaller replacement did, so that was probably dried up or something too. Still waiting on a caps lock key switch replacement and I need to get a replacement for C51 (forgot about it, 4.7uf 35v axial cap) just to get it all completely restored and proofed against future possible failure.

I also had a 1998 Sanrio Smiles Screensaver floppy disk arrive and I was able to image the floppy successfully, but the actual screensaver install doesn't seem to work. The installer generates an empty/0KB sanrio.scr file in c:\windows and then complains that it can't find sanrio.scr. It also doesn't show up in the windows screensaver menu at all. It doesn't work under windows 3.1 or windows 95 on two different machines so something is fundamentally wrong. So I'm a bit stumped on this one. If anyone might know what's going on I'd love to hear any ideas. On the upside the floppy disk doesn't seem to have any issues in and of itself, so I was able to get all the files off and archived when they previously were not. I wasn't able to find any mention of this floppy anywhere so I guess I kinda got to save some lost media at least. The screensaver floppy image file and all the extracted files are on the internet archive for those that want them. (Not sure I can link them here because it's technically copyrighted stuff.)

Started my Epox ep-9nda3+ machine to check something I suspected for a longer time. It boots without a GPU - the boot indicator clearly showing FF even without any GPU installed in the PCI or AGP slots. The nForce 3 on that board appears to be happy with that.

So I did start an RDP session and what do you know? It works just nicely. Perfect for it's current use for kernel driver and application development.

So that saves me a couple of Watts that would not be needed in the first place, I take that.

No way! What surprises me is that Windows actually works without a display adapter. What is the ATITool Utility?