• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

Solutions for HDI45 to VGA or DB15?

zezba9000

Well-known member
It looks like there's an available alternative: https://www.ebay.com/itm/New-Retail...-Programmable-Adapter-Converter-/283943104410

I don't know why eBay didn't show that when I searched for HDI-45, or maybe it did and I wasn't looking very closely.

The prices on the Apple originals are unfortunately quite high.

Other work-arounds would be to use a NuBus or PPC PDS video card, such as the a/v or the HPV card.
Awesome! Why o why doesn't Ebay show this when I search for it.
I now have two computers that have this port.

Thanks, this price is totally reasonable.
 

Cory5412

Daring Pioneer of the Future
Staff member
I was wondering if the vacation thing would be the bummer.

Weirdly, seems this is totally cyclical. There's lots of HDI-45 on eBay for under $30 right now. I saw one or two for $20, so if you haven't already placed your order you may find an original Apple one for a bit less, provided you have an Apple display or the next adapter.
 

zezba9000

Well-known member
HDI-45 on eBay for under $30 right now.
I got one of the converters from Walmart overpriced but it works. However computer doesn't fully startup until I hit reset button, then power cycle once. Its a Performa 6115CD.

So looking again, there was one on Ebay for 30$ I just ordered today. So now I can confirm if the 3rd party converter is less reliable then the official one or if its an issue with my Mac.
 

Cory5412

Daring Pioneer of the Future
Staff member
That's a known issue with the PowerMac 6100 and derivatives. It also impacts most earlier LC/II and I htink the III, plus the 475 and 605.

The solution you found, turning it on, then off, then off again in rapid succession is basically The Solution, until you can put a good PRAM battery in or otherwise feed the board the ~3v when you want to run it. (Two AAs was enough to keep the 475 from needing it but on my 6100, I just turn it on, do the PowerToggle, and leave it running until I'm Good And Done, usually a couple weeks later.)
 

CC_333

Well-known member
It also impacts most earlier LC/II and I htink the III, plus the 475 and 605.
The LC I/II/III aren't affected. It seems to be only certain late model '040-based Macs (such as the LC 475 and 605) and early PowerMacs (such as the 6100 and derivatives) that have this "quirk."

c
 

zezba9000

Well-known member
That's a known issue with the PowerMac 6100 and derivatives. It also impacts most earlier LC/II and I htink the III, plus the 475 and 605.

The solution you found, turning it on, then off, then off again in rapid succession is basically The Solution, until you can put a good PRAM battery in or otherwise feed the board the ~3v when you want to run it. (Two AAs was enough to keep the 475 from needing it but on my 6100, I just turn it on, do the PowerToggle, and leave it running until I'm Good And Done, usually a couple weeks later.)
Ya I figured out it was the battery causing the issue. Also recapped computer and installed OS 7.6.1 from a MacSD.
Also upgraded ram I had around so its now maxed out at over 130mb
Works perfect.

Now I really want to get a L2 cache card but can't find any.
 

LaPorta

Well-known member
I have a 512k card kicking around. It isn't the big ones everyone wants, but it is something.
 

Cory5412

Daring Pioneer of the Future
Staff member
512k is just about all you'll ever find for these, even a 256k should help out. 1-meg caches theoretically existed, but I've seen maybe two or three accounts of them "existing" and "being used" in real life. Any cache and all should put a bit of pep in these machines' step, too.

The other thing I recommend that should help a lot, especially if you run any 68k software, is to install Speed Doubler 8. Among other things, Speed Doubler 8 has a replacement 68k emulation code path which significantly speed things up. The boost can be huge. It's enough that a 6200 (with its 16K of L1, which is the best theory as to why the 6200 did poorly at 68k emulation) goes from 10% of the speed of a Quadra 700 to around 150% the speed of a Quadra 700, in "general" tasks. (It's still bad in floating point specifically -- but so are all PPC Macs: the first Mac to be faster than a Q700 at floating point was the 533MHz digital audio, so that was always a weak point.)

(in 68k benchmarks, 6100s start at around 50% as fast as a Q700 at general 68k emulation, but SD8 should still boost that a fair bit.)

I'd say, keep up the search for the cache card. I've seen lots of great work on memory replication too so it may be possible that there's enough demand to justify new ones being built, that may be something to check with SiliconInsider on.

Prior to "G3 upgrade" or "Just buy a faster Mac :)" caches are some of the best speedups for this era.

The LC I/II/III aren't affected.

Good to know! I haven't ever had an LC III and the last LC I had was in ~2005 or so when I was still puttering around with chaining double-A batteries together to replace PRAM batteries -- which, worked well! but, at this point I'd say not to bother with PRAM in anything except Macs you'll pull apart frequently and don't trust to do the PowerToggle on.

With a power supply from 1993-1995 I'd say "hmmm, best not to risk it if you can avoid it, especially all that often" which is why the last time I used my 6100, I just let it run for weeks on end. It'd probably need a recap before doing that today, though.
 

Franklinstein

Well-known member
Sadly the 6100, if they didn't come with one, is often hard to fit with the requisite adapter for either the AV card or the more rare NuBus adapter. But if you have the option, an AV card (the 7100/8100's HPV card may fit but the VRAM SIMMS may interfere with the HD or CPU heat sink) is the best one because it's much faster than either onboard video or 90% of NuBus video cards, and they're usually a lot less expensive than trying to find both the NuBus adapter and, say, a Radius Thunder GT.
Or you could find one of the 2 or so Apple monitors that included the HDI45 connector.
 

LaPorta

Well-known member
I may sound like a scroodge, but thats why I have two machines that have HDI45s and three adapters: I don't want to be out one ever.
 

Trash80toHP_Mini

NIGHT STALKER
You got me curious, so I pulled down the 6100. The pin sockets are a tad less than .1" pitch (metric?) so why not just do a converter based on a PCB?

DumbAssVideoConnector.JPG

The pin array on the right to the right of the oddly pitched center section appears to be a full .1" pitch horizontally and narrower pitch vertically. Don't have square pins handy to see if they fit the socket, but machine pins, being round like the cable's pins(?) seem to fit very nicely. HD15 VGA or DA15 Mac connector section of the PCB would cover the monitor icon above.

I'll bet a printed shroud for the PCB could snap fit into the lug setup as on the real deal?
 
Top