I've just built a new PC and I've got problems with games that randomly crashes so I started doing some benchmarks to try and find any issues.
When I run Prime95 I get the following error:
FATAL ERROR: Rouding was 0.4995895355, expected less than 0.4
I can only think that this means that there is some issue with my RAM.
My PC specs are the following:
i7 7700k @ 4.5Ghz
32 (16x2) GB DDR4 @ 3200Mhz
Asus Maximus IX Formula
GeForce GTX 1080
The RAM is two sticks of 16 GB (Corsair Dominator Platinum, CMD32GX4M2C3200C16) for a total of 32 GB. I've enabled XMP in the BIOS to make them run at the marketed 3200Mhz and the voltage is automatically set to 1.35 (which is exactly what they are rated for) instead of 1.2 which is stock. I've tried increasing the DRAM voltage from 1.35 to 1.4 in 0.01 intervals but I'm still getting the same rounding error. When running the sticks without XMP at the standard frequency (2133Mhz) I don't seem to get any errors. My motherboard is supposed to be able to handle speeds of up to 4133Mhz so I can't see why this wouldn't work.
4 x DIMM, Max. 64GB, DDR4 4133(O.C.)/4000(O.C.)/3866(O.C.)/3733(O.C.)/3600(O.C.)/3466(O.C.)/3400(O.C.)/3333(O.C.)/3300(O.C.)/3200(O.C.)/3000(O.C.)/2800(O.C.)/2666(O.C.)/2400(O.C.)/2133 MHz Non-ECC, Un-buffered Memory *
Dual Channel Memory Architecture
Supports Intel® Extreme Memory Profile (XMP)
** Refer to www.asus.com for the Memory QVL (Qualified Vendors Lists).
* Hyper DIMM support is subject to the physical characteristics of individual CPUs.
Background (simplified):
When any computer starts up the BIOS reads the SPD tables programmed into the memory. You can download and run CPU-Z to see the SPD tables in you memory. The BIOS then uses the memory speed and memory timings from the SPD tables that corresponds to the CPU speed that is set in the BIOS.
XMP profiles were developed to allow automatically setting not only memory speed and timings automatically, but also memory voltage. So, with the added ability to increase voltage, memory manufacturers could program SPD tables that run the memory even faster with the higher voltages available, and do that automatically too.
But the whole concept of XMP is faulted because the person writing the XMP SPD table for the memory has no idea what motherboard, CPU, what other peripherals are connected to your motherboard, nor even how many memory sticks you have installed. So, XMP profiles are just a guess at what memory overclock will work for the widest range of motherboards, CPUs, memory, and computer configurations. They have nothing to do with what your specific setup is. ... they're just a guess.
Do they work? Sometimes, sometimes not. And even if they do work it is unlikely they are the best settings for you particular setup.
Memory setting (with or without overclocking) is best done by manually setting the memory settings in the BIOS.
I tried manually setting the memory settings in the BIOS (same values as XMP would set) while leaving XMP turned off but the system wouldn't even boot and just gave me a QA-Code 55.
Edit: Now trying to use XMP but lowering the frequency from 3200Mhz to 3100Mhz and this far I don't seemt to be getting the error any more. Will do additional testing and post an update.
I tried manually setting the memory settings in the BIOS (same values as XMP would set) while leaving XMP turned off but the system wouldn't even boot and just gave me a QA-Code 55.
"Overclocking is a slow and methodical process of trial and error, mostly error, often accompanied by cold sweats in the dark of the night....then you succeed."
I'd start out setting all the memory settings to their defaults (AUTO) and then work up from there.
try increasing system agent voltage,the memory controller is on 7700k not on the mobo. increase VCCIO and VCCSA voltage in small increments. from skylake oc guide
Quote:
Safe Voltages (TENTATIVE):
Vcore: 1.45v/1.4v VCCIO: 1.25v/1.2v
System Agent (SA): 1.3v/1.25v
Vdimm: 1.4v/1.35v
No Cache voltage or Input Voltage with Skylake
"Overclocking is a slow and methodical process of trial and error, mostly error, often accompanied by cold sweats in the dark of the night....then you succeed."
I'd start out setting all the memory settings to their defaults (AUTO) and then work up from there.
Problem is I don't have any overclocking experience whatsoever other than increasing the multiplier and voltage to clock the CPU. I just expected the XMP to be a quick and easy way of getting faster memory. If XMP has so many issues it's kind of false marketing to market the sticks at those speeds because most people don't know how to tweak this stuff manually if it doesn't work.
try increasing system agent voltage,the memory controller is on 7700k not on the mobo. increase VCCIO and VCCSA voltage in small increments. from skylake oc guide
Thank you! I'll try running my sticks with XMP and 3100Mhz (down from 3200Mhz) for a while to see how it turns out. Those 100Mhz isn't going to make any difference in games anyway. I've now run Prime95 four times for five minutes each and not getting any errors. Before I got errors every single run. If I keep having issues I'll try your suggestion of modifying the System Agent Voltage!
The problem with xmp isn't the sticks. It's never the sticks. If they're rated for 3200 at 1.35v they'll run those frequencies. It's the CPU's IMC that's to blame.
Problem is I don't have any overclocking experience whatsoever other than increasing the multiplier and voltage to clock the CPU. I just expected the XMP to be a quick and easy way of getting faster memory. If XMP has so many issues it's kind of false marketing to market the sticks at those speeds because most people don't know how to tweak this stuff manually if it doesn't work.
Like RacistSunflower says, it's not the sticks, they'll run at the XMP speed and timings (probably even faster). But your memory controller won't do that, at least without overclocking it.
Why did you buy a fancy overclocking motherboard if you can't overclock? That's what your board is for! Now is the time to learn...................
Yeah, it's not easy, but many, many of the people here have put in the time and effort and have been greatly rewarded.
It's just a matter of read, read, read, try, try, try, fail, fail, fail ...then you succeed!
fwiw, maxing out the GB/Module (64max ram/4 dimm slots=16Gb stick) could be why you are having an issue. more ram=more stress on the IMC. so it would be reasonable the cpu's imc needs a little "help" (voltage increase).
That worked well! Since 3100Mhz worked without issues I simply had to increase both VCCIO and SA by 0.01 and after that 3200Mhz runs fine without errors as well!
As a side note. Yesteday I realized that you have to make sure your graphics card is fully inserted into the PCIe slot. By random chance I checked some stuff in CPU-Z and noticed that the Buss Interface was using "x1" instead of "x16". I pushed my graphics card harder into the slot (after turning off the PC of course) and it "clicked". After restarting the computer it now said "x16" and I gained 50-150% fps increase in all games. Makes no sense how the card would actually run at all without being fully inserted. Makes me wanna try inserting the CPU upside down to see if all calculations are done backwards...
That worked well! Since 3100Mhz worked without issues I simply had to increase both VCCIO and SA by 0.01 and after that 3200Mhz runs fine without errors as well!
As a side note. Yesteday I realized that you have to make sure your graphics card is fully inserted into the PCIe slot. By random chance I checked some stuff in CPU-Z and noticed that the Buss Interface was using "x1" instead of "x16". I pushed my graphics card harder into the slot (after turning off the PC of course) and it "clicked". After restarting the computer it now said "x16" and I gained 50-150% fps increase in all games. Makes no sense how the card would actually run at all without being fully inserted. Makes me wanna try inserting the CPU upside down to see if all calculations are done backwards...
well the pci-e 16x is like an electric standard that has 16x capacity. some cheap mobo manufacturers make pci-e slots that look like full 16x but have half the traces removed so they work as 8x. I can totally see a 16x card working @4x if the connection is not proper. CPUs don't work that way.
the vcsaa voltage bump had to work. if the sticks are rated for 3200 then it's just a matter of voltage for the imc. just like the cpu frequency,when you get a sample that will run 4900MHz at 1.3v but sb else's will only do 4500MHz on the same voltage. some imc's will be able to take 3600MHz ram while you sttruggle to get 3200 stable.
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