Originally Posted by dadi_oh
Good point. Not sure how much the pump draws. And for that matter I do have 5 fans on this system all running on 12V. 2 X 120mm Antecs, 2 X 120mm on the swiftech rad, and 1 ASUS NB fan. That might add up. I can't find a current consumption listed on the Antec site.
I have a clip-on current meter. I think I may try checking how much current is being drawn by the various components. Maybe the 450W isn't going to be enough either. Maybe I am in the market for a power supply... Recommendations?
The plot thickens... or is that "thins"? I think I am getting closer to solving this.
I went out and bought a new OCZ Stealth Stream 600W supply which rules out any power supply issues.
I decided to monitor what was happening with my actual Vcore on the GPU and discovered something interesting. Right now I have: vid5 - shorted vid4 - open vid3 - open vid2 - shorted. According to the chart this should give me 1.2000V on the core. I grabbed my trusty Fluke meter and measured the actual voltage and got the following:
idle = 1.2100 (i.e. 10mV above spec)
Not a big deal but here is the interesting part. I get different load voltages depending on what benchmark I run and also what core voltage I have set. For example, when core is set to default 700MHz and Proxycon benchmark is running the Vcore rises to between 1.234V and 1.240V. i.e. goes up by about 25-30mV or so.
Now remember in my past post I was saying it always crashed at the same point in Firefly Forest? When it hits that exact location the Vcore peaks at 1.246V. It did not crash however since I am only running at 700MHz core. Both Canyon Flight and Deep Freeze are similar to Proxycon, peaking at about 1.240V. So Firefly Forest draws more power for some reason
So next I set the core frequency to 840MHz and ran the benchmark. Well this time Proxycon hit about 1.244V peak (or about the same as Firefly at 700MHz core). Once it finished Proxycon and started Firefly Forest the voltage jumped up to about 1.248V. At the exact point that I have observed the crashes it did, in fact, crash. At that point voltage was 1.250V. The voltage then dropped to 1.000V exactly and the computer required a power cycle (same as when I had the 400W Antec so it was not the supply doing that).
So from what I understand about the overvoltage protection (OVP) it would have dropped to zero volts. So now I am thinking this is OCP (Over Current Protection) kicking in.
So now I will do some searching to see what drives the OCP and whether there is a work around. Back when I was investigating overclocking my X1950PRO I remember reading that there was a mod required to increase the switching frequency of the circuit supply Vcore so that it could supply the extra current required in OC. Maybe something similar applies here?
Another thought... Could this be a sign that I need better cooling on the MOSFETS? I just attached some heatsinks to the FETS with 3M thermal tape. But would OCP be aggravated by cooling of the FETS?
Looking for ideas.