Silent_Scone :
Crashman :
Silent_Scone :
Crashman :
Silent_Scone :
What is the return voltage from the DIMM? It's not a power supply lol.
You would need to measure at the socket (if you take into account losses along the power plane). This is about as accurate as you can get to showing how much voltage the memory is receiving. Like I've mentioned, you'd need a scope to measure this properly.
The applied voltage needs to be adequate enough that it makes allowances for the peak negative undershoot. On top of this, the measurement points are tapped at different points of the power plane depending on which model you are using, so the comparison is not valid.
I'm a little disappointed that you'd add a comment on blame basis for something like this at the end of a paragraph. Without the proper testing methodology, knowledge and data to show it.
It seems rather petty for a long standing site. Perhaps we'll see some results in future.
Er, blame basis? Historical context. The time when one could simply list the problem and everyone knew the name of the product has long since passed, the product is no longer produced, and that company is no longer in the memory business.
As long as I'm getting the same reading from the slot as I'm getting from manufacturer-specified hard-wired voltage check points of high-end boards, either I'm doing it well enough or the manufacturers themselves are doing it (voltage check points) wrong.
Well, it was yourself who posted regarding attempting to blame a single manufacturer.
So now you are measuring from the socket? Sorry, did you measure from the socket or not? As a moment ago you claimed you didn't measure from the socket because you thought you'd be "measuring the return power from the DIMM". Which in itself shows a serious lack of knowledge (and at this point tact also).
Only trying to offer you some advice here, you still need an oscilloscope to measure this correctly.
Oh boy, just read what I stated OK? I'm getting the same reading from the DIMM slot as I'm getting from the voltage check points provided on high-end boards by the manufacturer, so if I'm taking the reading from an invalid point so are the board manufacturers. And the history of why companies have added voltage goes back to instability most notorious to a single product that is no longer worthy of discussion in anything more than a historical perspective. To imply that this would be an attempt to defame a brand is to miss the point.
I don't know how you can justify labeling as DIMM voltage anything that's not reaching the DIMM slot, but I'm sure you'll find supporters.
Thomas,
Apologies if I am rattling your cage here, but your reply "not measuring the return voltage from the DIMM" isn't something you can downplay at this point. Professionally, it shows you are out of your depth and not qualified to publicly call out practices or in this case over-voltage at this level. It's best to leave those things to people who understand these things better, and stick to things that you are better qualified to proclaim.
The real time voltage and the VID in BIOS are not one and the same. This is because any power delivery circuit is susceptible to transients. As I've already mentioned a few times (which you've actively ignored), this is why an oscilloscope is needed to confirm whether the DIMM is really being subjected to overvoltage.
You keep rolling back to someone must be doing something wrong, but in this case it is you who is doing something wrong. A multi-meter is not the right tool here. At 5-20mv levels, this will likely fall within bounds of the undershoot of two phase power delivery systems.
If you really understood this, we wouldn't be having this back and forth. A multi-meter or any onboard voltage monitoring is not capable of measuring this, which is something you're failing to acknowledge.
Ah crap, let me bring you down to my level, there's still a supply voltage that's supposed to be constant right? And what I'm saying, is that my meter measures correctly the supply voltage on regular office PC boards. And what I'm saying is, the same pins measure about 20mV higher on *most* boards that are designed to run overclocking RAM. And, what I'm saying, is that this is the supply voltage we're setting in BIOS, it's the voltage the motherboard itself is supposed to be measuring in the status report, and it's the voltage motherboard manufacturers are tapping with their voltage detection points. It's also the voltage that appears on several of the pins on the module, and, the measurement at that pin is the same as the measurement at the manufacturer's volt check point.
Now, I'm saying that if a manufacturer says "Check the voltage here" and you say "That voltage doesn't mean anything", you're saying that the manufacturer is wrong.
So, say I have some RAM that overclocks to DDR4-3502 at 1.375V, DDR4-3468 at 1.370V, and DDR4-3434 at 1.365V, and that this has been confirmed on several boards using a volt meter.Consistency.Even if the reading is wrong, it's wrong in exactly the same way each time.
So I grab those three high end boards At default settings the firmware of all three boards reports that they're automatically configured to 1.35V, yet my meter shows that one board has 1.375V supply voltage, one has 1.370V, and one has 1.365V. Low and behold, one board supports stable overclocks to DDR4-3502, another to DDR4-3468, and the third to DDR4-3434. Yet when I manually set all of these to the voltage that corresponds to a 1.35V meter measurement at the DIMM, all three overclock that same memory to an identical DDR4-3400.
You say "don't do that, you don't have an oscilloscope attached to the CPU socket". And I say "if it's DIMM voltage, it should be attached at the DIMM". When I say a voltage is High, I'm not talking about Signal High, I'm talking about the reference point to which signal high and signal low would be based.
From the CPU side, I have a Core i7-6600K that I know will start to lose DRAM overclocking capability somewhere between 1.365V and 1.370V. So I put it on those same boards, and the one that measures 1.375V with my meter only reaches DDR4-3366. I drop the voltage manually 10mV, and the overclocking capability increases to DDR4-3434. The one that measures 1.370? I drop my CPU in there and it only reaches DDR4-3400. I manually lower the voltage by 5mV, and the overclocking capability goes up to DDR4-3434.The third board, which was previously measured as producing 1.365V at the DIMM, reaches DDR4-3434 with the lower-quality CPU, without manual recalibration. That's the same DDR4-3434 that I got from my other CPU at 1.365V. **This less-voltage-tolerant CPU appears to be a perfect secondary device for confirming DDR4 voltage too high, without even having the need for a meter.
The fact that all three reach the same overclock when manually set to the same supply voltage should be indicator enough that all three SHOULD be set to the same supply voltage. Apples-to-apples, right? I mean, there are some boards with crappy trace routs that get signal degradation at super-high data rates, that's why we keep getting faster RAM to look for those limits.
So tell me again, why am I not supposed to read the one voltage rail that the manufacturer tells me is VDIMM, and that goes to several pins on the DIMM itself?
An oscilliscope would show me a wave form. It would let me see the peaks. But I'm not talking about peaks, I'm talking about reference points. Centers. Which should be damn close to averages. Which is what a volt meter shows.