Intel i7 2600k Sandy Bridge Overclock
Sandy Bridge is known to break 4.3GHz – 4.6GHz with out much work and there are a smaller group that are willing to push their CPU’s really hard by using maximum vCore and turning up the multiplier. We have even seen a 5.2GHz overclock on air with an after market cooler from the ASUS camp on their top of the line motherboard. For the record the MSI OC Genie button gave us a perfectly acceptable 4.2GHz for an impressive 800 MHz overclock simply by pressing a button.
Being this is Legit Reviews and the fact we had this water cooling rig left over from our i7 870 we wanted to see if we could do better. This is where we ran into some interesting issues that made us think there is something wrong with either the BIOS or the motherboard itself. We made sure we had updated the BIOS to the latest on the MSI web site, version 18.5 prior to attempting to overclock the board.
You can see that we had no problem hitting 5.0 GHz by pushing the vCore up to 1.44 and it was perfectly stable under 15 minutes of Prime95. But we figured if others can hit 5.2 GHz on air it should be no problem on water.
Next we pushed on moving our vCore to 1.45v and tried 5.1GHz but the interesting thing is that CPU-z still reported 5.0GHz on this MSI Z68A-GD80 board. We tried using an older version of CPU-z but it also reported 5.0GHz. We thought there might be an issue with the board reporting at 5.1GHz so we tried 5.2 and 5.3GHz to no avail. CPU-z kept reporting 5.0GHz and even MSI’s own control center never would report above 5.0Ghz.
Something really odd was going on but was it the BIOS or the Motherboard itself? While we know that no two pieces of hardware will ever overclock the same, we also knew the i7 2600k has done over 5.0 GHz on other motherboards.
You can see from this screen shot of the BIOS the version is 18.5 and clearly we have the multiplier set to 53 for an overclock of 5.3 GHz but the system refused to report anything higher than 5.0 GHz. We were not sure if this was simply a reporting issue or if the board would not overclock beyond 5.0GHz so we ran Cinebench and found a marginal improvement between 5.0 and 5.3 leading us to believe it is possibly running higher than 5.0 but not 300MHz faster. We doubted it was a reporting issue at this point and something more significant was going on.
We contacted MSI about this bizarre issue and they quickly sent us a new version of the BIOS, v 18.6B4 (Beta 4), which we quickly flashed our BIOS with to see if that resolved our maximum 50 multiplier problem.
Unfortunately the beta BIOS did more damage than good and locked the multiplier at 34 so we could no longer overclock the board. We tried rolling back to the 18.5 BIOS image but no good, we were still locked out of changing the multiplier. We could change it but when we saved it would just go back to 34. Next we tried using the OC Genie button to see if that would do anything but to no avail. This lead us to think something else is going on and we possibly had a bad motherboard.
We again contacted MSI and they sent us a second GD80 overnight but we ran into the same issues. At this point it was obviously a BIOS issue which is too bad because the board seems to be pretty decent from a hardware perspective. We were about to publish this review when MSI had us work directly with some of the folks in Taiwan and they shipped us over yet another beta BIOS, version 18.6B5 (beta 5) and had us do a full DOS BIOS flash.
Well the good news was the new beta BIOS that they worked on overnight to send to us did the trick. It cleared the locked 34 multiplier but would it allow us to overclock beyond 5.0 GHz and report it correctly?
52 multiplier for 5.2 GHz overclock at 1.5v. Very stable, as shown below after 15 minutes of Prime 95.
We tried 5.3 GHz but while we could boot and use the system it would BSOD under Prime 95 and we had pushed the vCore to 1.52v for that multiplier. If we were gusty I am sure we could have tried for 1.55v on the vCore but we are not fans of replacing our CPU’s just for a screen shot.
We were pretty happy with this 35% bump in performance even after going through the pain of dealing with BIOS issues from MSI. MSI told us they were aware of this issue for this motherboard and will be releasing the full version of the beta BIOS they created for us shortly. As long as you stay under 5.0 GHz this shouldn’t be an issue but extreme overclocker’s be warned of this pitfall currently on this Z68A-GD80 MSI board.