As arjepsen already said, and as I mentioned further above, the ProBox does NOT do anything related to handling audio that would be recorded to your DAW.
It lets you start the D8B in a mode, that lets you move the faders and knobs on the D8B, and have the faders and knobs in your DAW move in response. No audio passes through the ProBox AT ALL.
The ProBox allows you to use the “Monitoring’ features on the D8B, still - in a similar fashion as the Mackie Big Knob - but it would just pass stereo signals (aka already summed mixes that you would sum elsewhere… not in the D8B) that you feed into the monitor section of the D8B, back out to speakers connected to the D8B (you can switch between different monitors and connected audio sources this way and adjust the volume), but that’s it. There’s no audio going over the USB connection to the computer.
Other than when you said “or sometimes record your band”, IMO you don’t need either the D8B or the HDR to RECORD. For that, either is complete overkill and complicates your recording chain, IMO. If your familiar with the DSP FX in the D8B and want exactly those, then maybe it would be worth it to you… but without wanting to ruffle any feathers on here… a lot has happened in the past 20 years, when it comes to the quality of DAW plug-ins. The D8B is frozen in time at the technological and audio quality standards from the early 2000’s. You can get great results with the D8B, but the plug-ins can’t do anything you couldn’t do with more recent plug-ins in a DAW (…and more often than not, those modern plug-ins will have an edge over those in the D8B). And no - you can’t run the D8B’s built-in FX in a DAW. Not with the ProBox and not without it.
A computer with a DAW and a simple audio interface with 2 pre's and inputs would be enough to build drums inside your DAW and record yourself over that interface (e.g. vocals, then mono guitars. You’ll need 2 inputs to record a stereo source like a keyboard as audio, etc.). Audio interfaces like that start at under $100, and I know people who did entire albums this way (…in fact this is quite common nowadays - at least for electronic music where canned drums are the norm).
IMO, the D8B and HDR make sense, when you need a lot of inputs and several pre-amps at the same time. So, if you want to record “your band”, I assume you mean you would be recording real drums (i.e. typically, you’d need anywhere from around 5 inputs to however many things you want to close-mic on a large kit… up to 12 inputs, if restricted by the pre-amps the D8B has on board)… and if you want to record the rest of the band live along with it, then as many additional inputs as there are players (or more if any of them output in stereo).
If you would NOT record real drums, but just 5 guys playing to a drum computer or something, the D8B would STILL be overkill, IMO. I’d just get an computer audio interface with 8 inputs instead… haven’t looked lately, but those should start around $250 (cheap Behringer or something).
Mixing is another story again. You could mix everything down in the box and without involving the D8B… but if you want to mix a song you composed via the DAW on the D8B, you need those audio channels to get over there, so you need a lot of OUTPUTS on your audio interface. And since your I/O cards are 3x DIO-8, you need an audio interface with ADAT-optical or TDIF (long discontinued) ports. Ideally 3 of those ports, since each handles 8-channels of audio at a time. There’s not a lot of audio interfaces that handle that many ADAT channels at the same time (I don’t think there is one that does 24-channels of TDIF… maybe early MOTU 2408’s or something), so unless you go “Pro” (aka Pro Tools HD/Native or an expanded Lynx Aurora or something), you would need to stack multiple audio interfaces just to reach the needed digital channel count.
That’s why I’m saying that you should have a clear vision HOW you want to use the D8B. Doing some of these things like in a “normal” setup, would require you to buy quite a bit of expensive gear for your DAW computer, to get it to interface with the D8B at the full I/O for the Tape I/Os.
If you don’t already have an audio interface with 8 channels of ADAT on it, then I’d recommend to plan on getting the D8B and the HDR to work together again, the way you had it working before. This way, your workflow will be the same as when you used that setup in another studio for the past 10 years. (Your workflow would be A LOT different, if you’d want to replace the HDR with a DAW… you’d basically have to learn how to use it all over again). You could then use this combo to record your band… and when you’re done, you could even bring the recorded audio over to your DAW for continued processing and “in the box” mixing if you want (…bringing it back to the HDR is a bit trickier). But often it will make more sense to just mix via the D8B/HDR combo and without involving the DAW at all (to keep things simple, and painful file transfers to a minimum) - especially if you also have any outboard FX to tie in. The D8B makes using outboard gear very straight forward (if familiar with standard studio workflows).
I’d probably use the DAW computer separately and switch between them depending on what you’re doing, and transfer the audio recorded on the HDR to the computer as needed… and then plan on expanding your DAW setup to integrate the D8B a bit later, when you have a clearer concept how many channels you need to be sending between D8B and DAW at the same time, and how you would solve this, technically (e.g. lots of I/O on new audio interface).
Now to the technical issues:
You have two memory sims in the “newer” bank of memory and nothing in the old bank. This should be OK, but just to be sure you start with a clean slate, here’s what I’d suggest:
1. Remove ALL the cable connections from the rack unit (e.g. with other gear (in this case an 8-channel MIDI interface), I saw cases were power entered gear the “wrong way” and was stored in a capacitor or something that made the unit malfunction, until the connected device that caused that was disconnected for long enough (a day) and allowed the power to drain from all components)
2. Pull the battery again, and this time, make sure to leave it out for 24 hours (it’s true that 5 mins are usually enough… but it’s not working right now, so lets try leaving it out for longer)
3. Make sure you put the “Clear CMOS” jumper back to how it was originally or remove the jumper completely (but save it), if your not sure about the correct position. If this is in the wrong position, the D8B will not boot and the symptoms would be similar to what you’re describing.
4. For troubleshooting, remove ALL the cards (but remember where they were installed, before).
5. Remove one of the two memory sticks (I think the slot closer to the processor is the one you want to use if there’s only one).
After it sat like that for 24 hours do this:
6. Put a new battery in the D8B (unless you recently did, already… putting the old one back in is an invitation to having to do all of this another time)
7. Put ONLY the video card back in. None of the other ones.
8. Connect your monitor to the video card, as well as your keyboard and mouse and power. Nothing else. Power on your monitor-screen to make sure you’d see any output from the D8b right away, and don’t miss it if your monitor would only start doing it’s power-on cycle when the D8B start booting up.
9. Have your camera ready and power on the D8B. If anything appears on the screen, take a picture and share it here.
If you DO get any out put on the screen this time, then you’ll need to go into the BIOS again to change the settings to what’s described int he database (you need to be very exact with that. If you’re not, we’re going to be going in circles here for all time).
If you still didn’t get any output on your monitor, switch out that single memory stick with the other one you have, and try again.
Let’s try all of that first, and see how far you get. Hopefully this will bring us back to you seeing some sort of error-message that we can base further troubleshooting on. If you still don’t get any output on the screen, it’s time to get one of those little mainboard speakers, so you can listen to what error beep-code the mainboard outputs (3x long beeps followed by a pause is usually a memory problem if I recall right… but lets see, maybe this won’t be necessary).
OK, I hope I didn’t forget to respond to anything you asked, but lets start over with this sort of thing.
…If you already have the other rack unit, though… have you tried connecting a monitor and keyboard to that and power it on (you don’t need to connect the D8B console to try if the rack powers on, at least)? Maybe if you don’t want to jump through all the hoops above, it would make more sense to just apply the crack to that one, and start using it, while casually troubleshooting the other rack unit whenever you have some extra time.
Sorry about the novel… I know I’m way too wordy, but type as fast as I talk, so I was basically just rambling on for a while over here