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Reply To: Dreamcast sync issues w/ firmware 0.77a

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#15459

pelvicthrustman
Participant

Just got my OSSC 1.6 and can confirm this issue is still present. Same symptoms described by the OP. Everything is perfect, then intermittent black screens and eventually no signal. I was playing Phantasy Star Online on the Dreamcast at the time for about 15 minutes before the issue presented itself. I am using the recommended DTV setting and a Kuro VGA box with a brand new VGA cable. I’ll try to reproduce the issue and see if I notice anything else. Does anyone know if there is anything I should try or anything helpful to look for?

Update:
I just tested the same scenario (PSO on DC via VGA) and I am quite sure that the problem is in fact thermal.
Here is the timeline of my testing:

– 15 minutes in game –
First loss of HDMI signal

– 21 minutes –
Second loss of signal event

– 22 minutes –
Third event, signal becomes intermittent at this point, occasionally recovering for up to a minute

– 26 minutes –
TV reports unsupported signal (audio stutters through for a second or two every minute or so but no picture)

– 30 minutes –
No change in 4 minutes, I restart the OSSC by toggling the on/off switch, the test pattern appears, I set AV3 input, everything works, a few seconds later the signal drops again, and returns intermittently

– 32 minutes –
Once again total loss of signal, I turn off the OSSC and leave it off for 30 seconds, once set back to AV3 the signal is back and stable

– 35 minutes –
Signal drops again

– 36 minutes –
Constant signal drops, I turn the OSSC off and leave it off for one minute

– 37 minutes –
Back on, signal stable

– 40 minutes –
First signal drop

– 43 minutes –
Total loss of signal, I blow onto the small copper heat-sink visible through the hole for the power switch for 15 seconds, the picture returns and is stable for several minutes

I repeated the last procedure a few times for sanity’s sake: Wait for the signal to stop completely (not intermittently dropping) and then restore the signal simply by blowing on the heat-sink. For reference, the room was around 20 degrees Celsius.

It seems that either my heat-sink was seated improperly at the factory or that the heat-sink itself is of insufficient size (albeit barely – the tiny amount of heat build up removed by blowing on the heat-sink shows that it is very close to being able to dissipate the necessary thermals).

Not sure what to do about this, but hopefully this helps someone, I really don’t want to return this thing to the UK (I’m in the USA), but I also don’t really feel like installing a new heat-sink – although that seems like the best course of action at this point – assuming I can find a bigger one that will fit.