Quick Question: if CPU support up to 2.4GHz, why would a MB support memory speed up 3.8GHz?

Happy Hopping

Happy Hopping

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But Even if you over clock the memory to 3.8 GHZ, the CPU can only sync. with memory speed of up to DDR4 2.4GHz, so are those over clock speed going to down step back to 2.4GHZ?
 
Happy Hopping said:
But Even if you over clock the memory to 3.8 GHZ, the CPU can only sync. with memory speed of up to DDR4 2.4GHz, so are those over clock speed going to down step back to 2.4GHZ?
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No, that's only an "officially supported" stat. It is running at 3.8Ghz.
 
you mean the CPU can support memory up to 3.8GHz, but do you have to overclock the CPU to achieve that?
 
Happy Hopping said:
you mean the CPU can support memory up to 3.8GHz, but do you have to overclock the CPU to achieve that?
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I believe that is the assumption. Remember too that the motherboard supports from the lowest bin to the highest of that cpu generation. So they also assume that if you are buying a high-spec motherboard that you intend to possibly overclock it. Ergo they tell you the upper limit of their memory support.
 
Happy Hopping said:
you mean the CPU can support memory up to 3.8GHz, but do you have to overclock the CPU to achieve that?
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You don't have to overclock your CPU, the memory is overclocked usually via an XMP profile built into it and may or may not work at the overclocked speed depending on your CPU's memory controller. Most intel CPU's can use memory at higher speed then the ones they are certified for but this is not guaranteed the memory will however be able to be run safely and problem free at lower speeds.
 
I have seen Asus XMP before. But I am not clear if I use XMP, does that mean Asus is over clock both the CPU and the memory, or I have a choice of over clocking just the memory

because I can buy memory that are certified to be overclock at a certain speed, but Intel never really allow overclock on any of their CPU
 
Happy Hopping said:
I have seen Asus XMP before. But I am not clear if I use XMP, does that mean Asus is over clock both the CPU and the memory, or I have a choice of over clocking just the memory

because I can buy memory that are certified to be overclock at a certain speed, but Intel never really allow overclock on any of their CPU
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Just because a CPU multiplier is locked doesn't mean the memory can't be overclocked. Technically you can overclock locked CPU's by increasing the frequency, but the gains usually are pretty minimal. It's the multiplier that is locked on Intel non-K CPU's. XMP is basically the memory telling the motherboard that the memory is designed to run at x speed and x timings. Some boards have it disabled by default, others enabled, but basically if you run without XMP your memory most likely will be running at DDR4-2133 or DDR4-2400 depending on the board. When you enable XMP it will run at its rated speeds and timings. XMP almost always works with Intel but with AMD Ryzen, especially first gen, you may have some issues if you don't buy QVL certified RAM.
 
the RAM I have in mind is Kingston HyperX Predator and they should be lifetime warranty

I assume you guys have all used Over Clocked memory. Is there any downside? such as Lock up? OS crash? Application software crash, freezes, blue screen etc.?

because I assume the gain is approx. 2X the memory speed
 
Happy Hopping said:
the RAM I have in mind is Kingston HyperX Predator and they should be lifetime warranty

I assume you guys have all used Over Clocked memory. Is there any downside? such as Lock up? OS crash? Application software crash, freezes, blue screen etc.?

because I assume the gain is approx. 2X the memory speed
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if you see people here talking about ram any higher than 2666 it is technically overclocked. not if you buy ram rated at the "overclocked" speed you want. no not 2x.
 
alright, in view of all these, I'll save the money. The DDR4 boot up time should be 3 sec., that's fast enough for me, although I prefer instant. There is no delay after that anyway
 
RAM speed is independent of CPU speed. Clocks are esentially like teeth on a gear, the faster the clock speed, the more gears on the cog (device) thus the more data per clock is transfered or the more operations performed per cycle. Faster RAM clocks simply allow moer data to be sent to and from the CPU per cycle.

If the CPU is choking on the data it is getting from the RAM, then a CPU overclock is more beneficial then a RAM overclock. If the CPU is waiting around for data to process, then a RAM overclock will be more beneficial.

All computer systems respond best to reducing the bottle necks.
 
I can't remember if I have ask this before: but if a motherboard manufacturer such as Asus has a motherboard that certified it can over clock the CPU and /or RAM to such and such speed, using for e.g., XMP profile, do they guarantee that I won't get a blue screen from windows?
 
Happy Hopping said:
I can't remember if I have ask this before: but if a motherboard manufacturer such as Asus has a motherboard that certified it can over clock the CPU and /or RAM to such and such speed, using for e.g., XMP profile, do they guarantee that I won't get a blue screen from windows?
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nope because the weakest link is the cpu's memory controller and/or the memory modules. all the motherboard manufacture can guarantee is that the circuitry/traces should be able to support up to those clock speeds but it's still dependent on other factors whether you can get those speeds. memory manufactures aren't even required to guarantee you'll hit XMP settings either since it's still considered an overclock even if they are sold at a specific rated speed.
 
Quick answer:

clever marketing (aka they mislead in clever ways)
 
Could somebody remind me what the OCP stands for in [H]ardOCP?
 
over clocking pages
It all started with the original Pentiums. You could change a few jumpers and get a Pentium 90 to 150 MHZ. Probably on Liquid nitrogen. lol
 
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Memory speed was only tied to the CPU speed when we were still using a FSB. Near the end of its lifecycle we could run memory asynchronously with non-integer multipliers. FSB was superseded by DMI and HyperTransport, and memory speed has been independent of CPU speed since then.
cjcox said:
Could somebody remind me what the OCP stands for in [H]ardOCP?
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Overclockers Comparison Page
https://hardforum.com/threads/frequently-asked-questions.835057/
 
Happy Hopping said:
alright, in view of all these, I'll save the money. The DDR4 boot up time should be 3 sec., that's fast enough for me, although I prefer instant. There is no delay after that anyway
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Boot up time doesn't really have a lot to do with RAM speed. Motherboards on some platforms do RAM training at boot up, takes a bit for the mobo to decide if the RAM is stable enough to continue with the boot process. Even really fast stuff.

The CPU data sheet will indicate the speed the RAM operates at. That's it. Mobo manufacturers can put some RAM speed in their specs, but every one of those that's higher than what the CPU data sheet says is an overclock - most mobo data sheets will have (OC) after every RAM speed greater than the CPU data sheet describes. RAM manufacturers can attribute a speed that they claim their RAM will operate at, and the good ones have a better chance of reaching the advertised speed - provided the CPU is a good example and the mobo is high quality enough. And they generally also have a disclaimer that the RAM might not operate at spec speed if the rest of the system isn't up to par.

Not a day goes by that there's not a post someplace from a guy that bought some whizz bang DDR4 4700 RAM and can't get it to run at 4700. It wasn't all that long ago that 4000 was the new world record RAM OC, these speeds are not usually plug and play. You might get lucky and get it to boot or even run - but RAM instability will trash your operating system as errors accumulate. Getting the RAM to pass a rigorous stability test at the speed you might limp to the desktop at is a whole 'nuther ball of worms.

I'll take stability over an arbitrary high clock speed any day. Sure, higher clock speed is nice and I'll take it if it's stable, but if it's not pretty friggin stable then you'll start getting BSODs, boot failure, programs not working, all sorts of issues until it just balls up and you have to reinstall the OS.
 
I second what Dullard said. it's exactly my pt. I use browser, wordprocessing and spreadsheet for 99% of the time. And these 3 software are already running at instant speed. I bought 1 PC game about 4 yr. ago, but never play it. So if over clock RAM is just a little bit of work, I'll do it, but if I need to do test to create a stable OS w/o the concern of BSOD, then forget it.
 
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