Just to update on this, apparently the 5820k (and other X99 CPUs) have a bug relating to AVX2, where after a few minutes of Prime 95 or IBT, they suddenly draw WAY more current than they need. This was causing me to hit the likes of 85-95C. I've since moved over to AIDA64 and get 55C max across 6 cores at 4.3GHz (HT disabled). I've managed to lower my vcore to 1.21v total too, with LLC on Level 5. How long do you guys bench for before you consider an overclock stable? I've had AIDA64 running for 40 minutes and so far so good.
So, update on the above. In AIDA64 I get to 55C max after an hour, but in gaming I'm hitting 85C. What do you think is preferable. Lowering the vCore and upping the LLC or lowering the LLC and upping the vCore. I get a hard lock if I lower it below 1.22v at Level 5 LLC.
TBH fella the H55 is pretty inadequate for a hex core Haswell. I really don't know why mine runs so cool I guess for once (and it would be the literal once) I won the lottery as I can do 4.6ghz on 1.23v and get max temps of around 68c. Can't you upgrade your cooler to the H80i or something similar like the Antec Kuhler 920?
I have to run Asetek coolers (the ones with the round block) since my board is 2011 v3 ILM - rather than standard 2011 v3. I've actually got a refurbed H105 arriving today - but it'll mean that I have to go back to air cooling my GPU which makes me sad.
The Antec Kuhler 920 was Asetek mate. http://www.antec.com/product.php?id=704370&pid=17&lan=us It was a seriously good cooler, too. http://www.bit-tech.net/hardware/2011/07/21/antec-k-hler-h2o-920/3 I strongly suggest hunting one down
Ah! Ok, discovered the issue - the fan on my CPU heatsink wasn't spinning up for some reason! I whacked everything to max speed in the BIOS and it barely breaks 50C at 100% load.
I've been running my X5650 at various speeds in the time I've owned it (almost 18 months) but yesterday I hit a wall - I replaced my Gigabyte X58-USB3 with a UD7 rev 2.0 and it doesn't very much like overclocking the Xeon X-series CPU even with the latest BIOS.
I've had to scale back the oc on my CPU to 4.2. Despite having no apparent issues while playing battlefront, I'd get a hideous drop in fps after 1 or 2 rounds which a lot of the time required coming out of the game to fix. Had a look at the known issues on the official forums and some were able to fix it after returning their cpu ro stock. I dropped it to 4.2 which will run comfortably on stock voltage and all seems well now. Disappointed but the jump from 4.3 to 4.4 required a large bump in volts and I haven't noticed a performance drop.
