I Helped Ownage yesterday with the vmod.
The voltmod did work, we could easly hit 600MHz+ on the core.
But we ran in one (big) problem; After 2min of ATitool "Scan for Artifacts" we got "no signal input" on the screen. At first we thought did must have been the 6K pencil resistance wich should handle the overvoltage protection. The resistance maybe (because of heat) did change a bit indeed. We did pencil it down for 5,95K but afther the first check-up it measured 6,24K. The next test session went the same, pencil it down to 5,98K and afterwards testing (and blank screen @ ATItool) it was 6,xxK again. Saying that it did use a normal reagular HB pencil instead of a more softer 2B pencil wich should probably get a more solid resitance.
Although this little deviation I discovered a even more reasonable explanation for the black/blank screen issue; The Digital-VRM (VITEC chip) get extremely hot. After the second check-up i did put my finger on the VITEC chip to get an indiction of how how the chip got...
With a reflex i put my finger back it was EXTREMLEY hot, for sure it was 100degree or maybe even hotter. Ownage, the owner of the card told me allready when I asked him about "hot spots/hot mosfets" that the VITEC got I little warm but I have done a lot of voltmods but I never got a "electric management supply" of the PCB that extremly hot. This VITEC chip could have been toasted. This maybe explained why mid-range cards do have Digital-VRM and the high-end cards don't at the moment, maybe because Digital-VRM is not the best solution for high-end cards like XT(X) series wich consume about 125watts of power. I think there's a little margin of the wattage this VITEC chip can handle.
The VITEC chip in question:
So for the thrid testing session we put a 8cm FAN with quite some airflow straight on the back-end of the card with tape so the FAN is putting airflow against the VITEC chip to cool it down. So resitance check-up and card back in. We played the game Just Cause and NFS MW for about an hour with no problems but clocking the core to 600MHz and "scan for Artifacts" with ATITool just resulted in a "No signal input" afther about 2min.
This all was tested in my system. I told him (Ownage, owner of the card) that he should put some heatsinks on the chip and the backside of the card en put some sufficient airflow on the VITEC chip. Because yesterday evening we did the voltmod en some little testing we didn't got the time to put his card under a big test of the issue I wrote above. He will test his card in his own system with some more time. So you will stay tuned, this is just the beginning offcourse.
Also check Ownage his updates here
@Ruffy91 what are your results? And what kind of cooling are you using?
The Vitec "Chip" has 2 Coils inside, they get very hot even @ stock voltage, but the Temperatur should not exceed 120°C
Are the 2 Strips that thermally connect the Heatsink and the 3 other small Chips (within the withe line) at the right place?
For Humans 75°C is as hot as they cant touch the hot spot.
Edit:I did measure it with Thermometer & Thermal paste, the surface is 70°C hot @Full load, but i cant touch it longer than half a second.
Last edited by ruffy91; Oct 17th, 06 at 03:00 AM..
Today i bought some conductive ink and tried the mod (1,35v)
I tried it three times and it didn´t work :/
Think it´s because of the resistor which needs to be penciled... but till now i penciled it 3 times ... 1st try was @5,96k Ohm than 6k Ohm and last time i penciled it to 5,93k Ohm... No succes @all... still 1,12v GPU.
Perhaps some advice? i´ll do the Fourth try now...