[SOLVED] i7-4790k cache voltage

sz0ty0l4

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Hi,
just gotmyself a 4790k today. going to try OC to 4.6 with around 1.25Vcore
question:
i'm planning to leave Cache ratio on default( 40x)
What should i do with Cache voltage?
some guides suggest 1.15, some say 1.85, some say 1.2... some say leave it on auto.

I tried setting BIOS to default, but i CANNOT check the default cache voltage. I tried: CPU-Z, HWINFO64, and Bios. and even Intel extreme utility, but all says " cache voltage: auto, or default, no proper value. ) is there a way to check default value? So i have an origin to go from?
 
Solution
If you leave the cache ratio at the default setting, then I would also leave the cache voltage at the default setting. I would only make changes to voltages for cache, ring, system agent, etc., if you change other settings like the ratio for a given setting. Anything you are not messing with, don't mess with. LOL.

Really it's not particularly necessary. That is a very mild overclock anyhow. The benefits from cache are minimal. Just worry about the stability after making changes to the core voltage and multiplier for now. Then work on memory. While overclocking, and until you have established 100% thermal and stability compliance, leave the memory at the default non-XMP configuration. Work on the XMP, overclock or tightening of timings...
If you leave the cache ratio at the default setting, then I would also leave the cache voltage at the default setting. I would only make changes to voltages for cache, ring, system agent, etc., if you change other settings like the ratio for a given setting. Anything you are not messing with, don't mess with. LOL.

Really it's not particularly necessary. That is a very mild overclock anyhow. The benefits from cache are minimal. Just worry about the stability after making changes to the core voltage and multiplier for now. Then work on memory. While overclocking, and until you have established 100% thermal and stability compliance, leave the memory at the default non-XMP configuration. Work on the XMP, overclock or tightening of timings on memory AFTER you have a stable CPU overclock.

If you want to go back after the basics are stable, then do so, but don't try tweaking those settings on the CPU as part of the initial process.


Quick and dirty overview of overclocking/stability validation procedure.

Set CPU multiplier and voltage at desired settings in BIOS. Do not use presets or automatic utilities. These will overcompensate on core and other voltages.

It is much better to configure most core settings manually, and leave anything left over on auto until a later point in time if wish to come back and tweak settings such as cache (Uncore) frequency, System agent voltage, VCCIO (Internal memory controller) and memory speeds or timings (RAM) AFTER the CPU overclock is fully stable.

Save bios settings (As a new BIOS profile if your bios supports multiple profiles) and exit bios.

Boot into the Windows desktop environment. Download and install Prime95 version 26.6.

Download and install either HWinfo or CoreTemp.

Open HWinfo and run "Sensors only" or open CoreTemp.

Run Prime95 (ONLY version 26.6) and choose the "Small FFT test option". Run this for 15 minutes while monitoring your core/package temperatures to verify that you do not exceed the thermal specifications of your CPU.

(This should be considered to be 80°C for most generations of Intel processor and for current Ryzen CPUs. For older AMD FX and Phenom series, you should use a thermal monitor that has options for "Distance to TJmax" and you want to NOT see distance to TJmax drop below 10°C distance to TJmax. Anything that is MORE than 10°C distance to TJmax is within the allowed thermal envelope.)

If your CPU passes the thermal compliance test, move on to stability.

Download and install Realbench. Run Realbench and choose the Stress test option. Choose a value from the available memory (RAM) options that is equal to approximately half of your installed memory capacity. If you have 16GB, choose 8GB. If you have 8GB, choose 4GB, etc. Click start and allow the stability test to run for 8 hours. Do not plan to use the system for ANYTHING else while it is running. It will run realistic AVX and handbrake workloads and if it passes 8 hours of testing it is probably about as stable as you can reasonably expect.

If you wish to check stability further you can run 12-24 hours of Prime95 Blend mode or Small FFT.

You do not need to simultaneously run HWinfo or CoreTemp while running Realbench as you should have already performed the thermal compliance test PLUS Realbench will show current CPU temperatures while it is running.

If you run the additional stability test using Prime95 Blend/Small FFT modes for 12-24 hours, you will WANT to also run HWinfo alongside it. Monitor HWinfo periodically to verify that no cores/threads are showing less than 100% usage. If it is, then that worker has errored out and the test should be stopped.

If you find there are errors on ANY of the stability tests including Realbench or Prime95, or any other stress testing utility, you need to make a change in the bios. This could be either dropping the multiplier to a lower factor or increasing the voltage while leaving the multiplier the same. If you change voltage or multiplier at ANY time, you need to start over again at the beginning and verify thermal compliance again.

A more in depth but general guide that is still intended for beginners or those who have had a small amount of experience overclocking can be found here:


*CPU overclocking guide for beginners
 
Solution

sz0ty0l4

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Thx for the answer. Actually i tried some settings and ran a 10min intel stress test which passed
4.6ghz -1.287
40x cache -1.16 ( lot of threads set i should set it manually to 1.15, and since it doesnt show a value on " auto" figured i'd tick around 1.16 just in case, but might modify it back to auto, problem is i cannot really seem to monitor this value at all.

Temps: during the stress test max temp was 87C on core 2, weirdly core 3 only 77C, but theres no difference in CPU USAge, or in clock speeds.
Difference to Tjmax: 13C
this on aircooler with 1x fan

What do you think??
Btw first i tried 1.265Vcore, but it crashed after 3 min of stress test, also its a pity i cannot do stress tests for a lot longer, because im not at home that much sadly to watch over it


Edit:

Set it back to 1.24V - 4.5Ghz, and Cache to 40x and Auto voltage. seems stable... been gaming with 100% cpu usage for 1 hour now. temps are around 75C peak
Stress test ran for 15min - 80C max temp

had 1 crash in quake, but only appcrash, not PC
 
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Any crash, is unstable. Doesn't matter why.

More importantly, the system does not need to crash to be unstable. And if it IS unstable, you are corrupting data. It doesn't matter if you just game or not. You game files will get corrupted, incrementally, every time you play a game and save data or levels, etc., it will be corrupted if it is not stable. If you are unwilling to do the FULL testing required to validate stability and thermal compliance, which by the way you are already 7°C above the maximum recommended temperature for any Intel Core-i processor, then you should return everything to stock and not bother with overclocking at all. Do the work, or don't do the work, but don't think to overclock without doing the work. It's a bad, terrible, really no good idea.
 

sz0ty0l4

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What i meant , is that the crash in the game, happened too previously aswell( with a locked i7-4790 that i had before, so i thought it's related to the game.
Either way i'm doing the tests you suggested now.
I've installed an exhaust fan at top, and my temps dropped by 15Celsius, Intel stress test maxes out around 72 package temp now...

I will download realbench and test for 8 hours tomorrow for full stability.

Thank you very much.
 
Sure, my pleasure. I see what you mean about the game crash, and that is of course very possible. Not every crash, for obvious reasons, is necessarily due to instability, BUT, it is ALWAYS good to make SURE of that though. Then, if it's otherwise stable, you can start looking at the GPU card drivers or the game itself.

Always a very good idea to do these things as well.

Here are the first steps to take when trying to solve these kinds of hardware problems. If you have already tried these steps, all of them, exactly as outlined, we can move along to more advanced solutions.

If there are any you have NOT done, it would be advisable to do so if for no other reason than to be able to say you've already done it and eliminate that possibility.


First, make sure your motherboard has the MOST recent BIOS version installed.

If it does not, then update. This solves a high number of issues even in cases where the release that is newer than yours makes no mention of improving graphics card or other hardware compatibility. They do not list every change they have made when they post a new BIOS release.

Second, go to the product page for your motherboard on the manufacturer website. Download and install the latest driver versions for the chipset, storage controllers, audio and network adapters. Do not skip installing a newer driver just because you think it is not relevant to the problem you are having. The drivers for one device can often affect ALL other devices and a questionable driver release can cause instability in the OS itself. They don't release new drivers just for fun. If there is a new driver release for a component, there is a good reason for it. The same goes for BIOS updates.

IF you have other hardware installed or attached to the system that are not a part of the systems covered by the motherboard drivers, then go to the support page for THAT component and check to see if there are newer drivers available for that as well. If there are, install them.

The last thing we want to look at, for now anyhow, is the graphics card drivers. Regardless of whether you "already installed the newest drivers" for your graphics card or not, it is OFTEN a good idea to do a CLEAN install of the graphics card drivers. Just installing over the old drivers OR trying to use what Nvidia and AMD consider a clean install is not good enough and does not usually give the same result as using the Display Driver Uninstaller utility. This has a very high success rate and is always worth a shot.

If you have had both Nvidia and AMD cards installed at any point on that operating system then you will want to run the DDU twice. Once for the old card drivers (ie, Nvidia or AMD) and again for the currently installed graphics card drivers (ie, AMD or Nvidia). So if you had an Nvidia card at some point in the past, run it first for Nvidia and then after that is complete, run it again for AMD if you currently have an AMD card installed.

Here are the full instructions on running the Display driver uninstaller and CLEAN installing new drivers.