I know you just mentioned that
"...no one has ever conclusively proven that to my satisfaction..." when it comes to UC'ing, but here is Tutor's BIOS set up here (on Post #70):
http://www.insanelymac.com/forum/index.php?showtopic=233891&st=60
"Here are my some of my underclocking results for my 24-7 settings of:
1. No changes in Signal Tweaks yet.
2. No changes in Memory Configuration yet.
3. Frequency/Voltage Control
Both CPU's - Without VDroop
CPU 0 Vcore boot - 1.2750
CPU 0 Vcore eventual - 1.3000
CPU 1 Vcore boot - 1.2675
CPU 1 Vcore eventual - 1.2875
CPU VTT both boot - 1.325
CPU VTT both eventual - 1.350
CPU 0 DIMM Vcore - 1.65
CPU 1 DIMM Vcore - 1.66
IOH 1.35
Everything else at default or auto for now.
4. Frequency/Voltage Control
No Dummy O.C.
Target CPU - 2.17
CPU Freq. - 167
PCIE Freq. - 103
CPU Multi - 13
QPI - 4.8
Memory Freq. - 1066
Everything else at default or auto for now.
5. CPU Configuration
Everything is Enabled and/or set to Auto, including the newly exposed C1E, except MaxCPUID which is disabled."
But just like you said (as well as Tutor)
YMMV... That's the thing, I'm always thinking
"...am I doing something wrong?" Since it's working so well for Tutor (regardless of my milage varying). I have the same equipment now (with the exception of the X5690; which I thought would be just slightly better than the X5680's when it comes to performance).
- Same OS (Mac OS X 10.6.7)
- Same 48GB of RAM 2000 MHz / 9-11-9-11 / 1.65V - it's a
matching set of Mushkin Model #993991 (I'm also a Mushkin reseller so I got a better deal and their reviews have been top notch on this particular set of RAM, that's why I got it and they are luke-warm to the touch in their OCCT CPU: Linpack TT (which BTW, I will call from now on OCLTT). I had the Dominator Corsair GT's Red Tops (2000 MHz / 9-10-9-11 / 1.65V) but it failed the MemTest86 as one of the sticks were bad and the tech support said that you need to get matching set of RAM and doing that would have been more than twice the price. I tried using the same RAM as Tutor's Corsair XMS3's but during the Stress Tests they ran hot to the touch (as they are low profile RAM with no real heat sinks to dissipate really any kind of heat).
- Same 4890 HIS 4890 Turbo OC'd GPU that produced artifacts as a result of it running very hot, (I think something happened as a result of the tests or maybe the card just failed). Now I'm using a Water Cooled Sapphire 2GB 4890 GPU which now runs warm to the touch during OTT. So I know that I have an almost identical setup, but enough of that now as I'm just venting...
I did take your advice and I'm now upped my Vcore to 1.45V and left the VTT alone at 1.35 (as you suggested), and so far I'm an hour into my test and no QUACKING. My temps are now around - 30C Low to 76C Peak in it's testing. Also for the OCLTT. Yesterday I was used the "Infinite" test setting, as opposed to the "Automatic" test setting. I don't know if that has anything to do with the testing, but I just switched back to the (manual) "Automatic" and input 24 hours (for it's testing). I hope 76C is at an okay level as I've never seen it go that high before. The SR-2 mobo is reading 69C and the Dual Bay Res is reading 32.3C at their peak. Again, if this is okay and I can keep this test going, then let me know.
Lastly, I have 165/100/13. Should the PCIE Freq. during this P3 OCLTT stay at 100 or should it go up to 101, 102 or 103? If it just needs to stay at 100 for this particular test then I'll just leave it be. Again, thanks...
😎
EDIT: The OCLTT just failed at 1 hr 43 min, so do you think I should up the Vcore to 1.46 and keep the VTT still at 1.35V? Remember my temps are up to 76C. If you think that bringing the
CPU Freq down a notch to
164/100/13 and keep it the Vcore at 1.45 and the VTT at 1.35V then I can try that. I'll wait for your reply. Thanks again...
🙂