Very dead system, help/advice needed please.

Hi all, have been running a hackintosh system (specs below) with very few issues the last five years. In fact i'd go as far as to say its been the most stable/reliable DAW setup I've used.....anyway



So this last week lots of different 9060/9061 errors, freezing when changing plugins...force quitting protools...general misery.



Ive changed pretty much everything to try & get to the bottom of the problem.



So far I've tried.



* Trashing all prefs

* Booting into both 10.6.x/PT8 HD & 10.7.x PT10HD (both have been used regularly before with no issues, & are on separate boot drives)

* changing the drive the session plays off (multiple times)

* Running digitest on the HD3 PCI cards (all passed)

* Using just in single 192D

* Swapping ALL THREE cards out for a spare set I keep

* Tracking with no plugins on



Basically, the only thing that works is booting into native on PT10, which at least allows me to mix & monitor via the Spdif out on a little USB interface I use for iTunes playback, & my pro control still functions.



So in essence, the TDM side seems totally F****d.



The only thing I've not been able to try is swapping the ribbon cables that connect the cards, as I don't have spares.



Any one any bright ideas? Could the motherboard be screwed on the PCI slots?



PT10 running natively with ZERO issues. btw, so the mac must be fine at a basic level.



Any help VERY appreciated :):)