I spent another hour or two messing around with the settings last night. At 4.8 GHz + LLC set to medium +0.015V, prime95 seemed fine after a few minutes so I was planning on letting it run all night. I decided to play games for a few minutes though and I got a BSOD with the following reference bug check from Overclockers.co.uk ''0x124 = increase/decrease vcore or QPI/VTT...have to test to see which one it is''.

 

Increasing it to 0.020V + LLC set to high might have fixed the problem, but I found the load voltage to be way too high so I stopped the test immediately and restarted into the BIOS.

 

Finally it was getting late so I settled for 4.7 GHz + LLC set to high/medium (can't remember I'll check tonight) +0.010V. The game ran fine for 2 hours and prime95 didn't crash for 5 hours. The game gave me MAX 60C while prime gave me max 83C during the night. I'll keep pushing it to try to get 4.8 GHz, if I can. Although I'm not sure 100 MHz will make a big difference, I'll see what I can do. I'm just trying to find the proper balance between LLC and DVID I guess.

 

As for the system going to standby, I don't think prime95 crashed because when the PC resumed from sleep, prime was still running and the CPU kicked back up to 60C almost instantly. I fixed it by changing the sleep time to ''never'' in the power options of Windows 7. I can't use the ''High Performance'' plan for some reason, as the CPU never downclocks on that setting. I use ''balanced'' with no sleep timer, it does the same job anyway.

 

I'll definitely look into a push-pull config. I'll then have the 2 CPU fans + the side intake fan; it should be a bit better. I'll pick up a 120mm fan next time I'm near a local computer shop.

 

 

I'll update you when I get new results!

LLC will add or subtract a fair amount of voltage, on my board it's ~0.035v per increment so leaving the offset at +.015 and raising LLC will effectively raise your voltage by another 0.035v. If you were relatively stable with medium LLC and an offset of +0.015v then I would stick with medium LLC and just raise the offset an increment at a time until you find what you need for full stability. If you get to an offset of +0.035v then raise LLC a notch but drop the offset down to +0.005 and start again. but I think you're getting close and from what you're saying possibly only need to go to around 0.025v on medium LLC.

I think you are absolutely right on that last prediction. I'm short on time right now, but I just tested a bit a got good results with the following settings: Medium LLC, +0.025V, 4.8GHz. 

 

I only did a few minutes of prime95 + 10 passes of IBT on high, but it usually freezes way before then. I will do a several hour prime95 test later. The voltages was at 1.416V during the test with 1 or 2 peaks at 1.428V, so I think that's good. The temps are cold too, only 70C on prime95 (for now) and 80C on IBT!!

 

I'll see what I can do with those settings and hopefully I'll get to installing FSX eventually.

 

Thank you!

Apparently on Gigabyte boards you need the following setting - Turbo Power Limit = 200, thought I'd just check you have this set as it would be good if you could get your offset down a notch so they not go over 1.424v and that setting may help. But as I said before in 24/7 use you're unlikely to reach the max volts and temps you get when stress testing, so you'll be OK if you're peaking at 1.428 in IBT.

 

The info regarding the setting comes from this thread - http://www.overclock.net/t/968053/official-the-sandy-stable-club-guides-voltages-temps-bios-templates-inc-spreadsheet/2240#post_14466483

Thanks for that link PieEater. Although that settings doesn't seem like it will actually do anything, I changed it from 95W to 200W (although CPU-Z still says my CPU's TDP is 95W, maybe it's unrelated).

 

Turns out my Medium LLC, +0.025V, 4.8GHz wasn't so good after all. I did work in prime95 for a good 10 minutes as I said before but it crashed a few days ago while playing a game. Giving it Medium LLC, +0.030V, 4.8GHz fixed that and was stable in prime95 for 3.5 hours BUT it gave me a top voltage of 1.440V which I don't like at all. I'm back on my 4.7GHz clock settings but I'll still try to get to 4.8GHz when I have a bit of free time. In the worse case I'll just fine tune my 4.7 OC and call it a day, I'm not sure all of this extra voltage really is worth 100MHz.

 

I'll keep trying! Thanks!

One last idea if you haven't done so already would be to see if there is a BIOS update for your board, Asus released an update for my P8Z77 that allowed me to go from a stable 4.7 to 4.8 at the same voltages etc.

 

Having said that, it may well be that 4.7GHz is your safe stable limit and looking at the SandyStable spreadsheet for 2500Ks this seems to be the upper average, the exceptions seem to either use voltages outside of the safety zone or appear to have increadibly good chips. I think you're right that running at 4.7 with voltages and temps nicely below the maximum is a better idea than running at 4.8 pushing the boundries, and in reality you'd not notice the difference.

Hi,

 

First off I just want to say sorry for not posting for a while. I have been busier with 'real-life' and don't have much computer or flight simulator time. However, after a few weeks of usage, I have decided to stay at 4.7GHz.

 

Like you said, I will probably notice no difference between 4.7 and 4.8 and I really prefer the lower temps and voltages for CPU longevity. 

 

Also, there is no BIOS update available for now, I'm running the latest version according to Gigabyte's website.

 

I might keep tweaking the voltages to get them lower if that can make the CPU last longer, but it currently works fine and tops at about 1.39 when using CPU intensive apps, with an occasional peak at 1.416V, such as in prime95.

 

When I get to FSX I'll keep you posted with the results!

 

Thanks again,

Thanks for the update.

 

Good plan to find the lowest voltage you can whilst maintaining system stability but as long as you stay within the voltage and temperature tolerances you don't really need to worry about CPU longevity. I've been overclocking for at least 12 years and have never had a CPU give out on me, admittedly I don't tend to keep rigs for more than 4 years but then few people do.

 

4.7GHz is a respectable overclock and will give FSX a nice boost as well as meaning you have a rig that should last you a good while.

Just thought I would let you know I have finally gotten to reinstalling FSX and a few addons. I'm quite impressed with the improvement over the stock clocks! I haven't done much yet, only having installed the PMDG MD-11, but I'm getting a solid 60 FPS in default SFO, inside the VC at 1680x1050, which isn't that bad!

 

I had quite lower FPS with my i3 if I recall.

 

I'll post again once everything is setup and working properly.