Rounding Error in Prime 95 with OC - Possible RAM issue?

[samx300]

Hi all,

I am getting a Rounding Error with Prime 95 on my new OCd Gaming Rig (The Nemesis). I have discussed the issue with PCS and I am providing details of the 3 scenarios where I ran P95. Any comments or suggestion would be greatly appreciated.

Default BIOS Info:
AI Overclock Tuner: Manual
BLCK Freq: 100.00
Turbo Ratio: enabled (all cores)
By All Cores: 46
Internal PLL OverVoltage: enabled
Mem Freq: 1600MHz
EPU Power Saving: disabled
Load-Line Calibration: regular
VRM Freq: auto
Phase Control: extreme
Duty Contorl: extreme
CPU Current Capability: 110%
CPU OverVoltage: manual mode
CPU Manual Voltage: 1.40V
DRAM Voltage: 1.650V
VCCSA Voltage: 1.1250V
VCCIO Voltage: 1.150V
CPU PLL Voltage: 1.81250V
PCH Voltage: auto
CPU Spread Spectrum: disabled
CPU Ratio: auto
Intel Adaptive Thermal Monitor: enabled
Intel Virtualization: disabled
Intel SpeedStep: enabled
Turbo Mode: enabled
CPU C1E: disabled

Scenario 1 (Suggested by PCS) - Default BIOS settings:
Running OC @ 4.6Ghz, DRAM @ 1600Mhz - 9-9-9-24 2T @ 1.65v
All was ok, no errors detected. CPU temps reached a max of 73 deg.


Scenarios 2 (Suggested by PCS) - Default BIOS settings, but DRAM settings changed:
Running OC @ 4.6Ghz, DRAM @ 2133Mhz - 9-11-9-27 2T @ 1.65v
There was a fatal hardware error on logical core worker 3 - rounding error during a stress test. CPU temps were in the range of 69-76 degs. Is this temperature normal with the ECO ALC?

Scenario 3 (My preferred OC settings) - Load Line Calib set to Extreme, CPU Multiplier set to 47, vcore still at 1.40v:
Running OC @ 4.7Ghz, DRAM @ 2133Mhz - 9-11-9-27 2T @ 1.65v
Fatal hardware error on logical core worker 5 - rounding error during a stress test. CPU temps were shockingly in the range of 79-86 degs!

Temps:
I think the temps (in general and especially in scenarios 3) are excessive with the CoolIT ECO ALC
OR
The ALC just doesn't do the trick for this system?

My request from Forum Members:

Please suggest the way forward. Is the rounding error due to the RAM? Could it be due to a faulty RAM module? Does this error matter during day to day gaming, music and general PC usage?

I have a sneaking suspicion that if I keep my CPU OC @ 4.7, and turn the RAM down to 1600Mhz, the rounding error will disappear. However, doing so will defeat the entire purpose of me buying the Hyper X T1 RAM Do you think my RAM is faulty?

Please, help a fellow gamer with his faling P95 tests and temperatures..

Anticipating a solution from all you geniuses out there REP will be awarded to all helpful responses.

The screenshot below is from Scenario 3 described above. (Please click on view image separately if the size is too small)

 

[Teaz]

Im not sure on the problem but with overclocking settings on and have the Eco, i believe thoses temps are pretty normal or reasonable to be that high so i dont think anything is wrong for the cpu temps. unless someone who could correct since after the testing is set to extreme so it should be normal for such temps.

not sure abou the ram problem though so cant help with much info

I would avoid mega or alot of benchmarking with ssds though as its pretty unhealthy from the last time i checked. which was not very long ago.

 

[samx300]

Im not sure on the problem but with overclocking settings on and have the Eco, i believe thoses temps are pretty normal or reasonable to be that high so i dont think anything is wrong for the cpu temps. unless someone who could correct since after the testing is set to extreme so it should be normal for such temps.

not sure abou the ram problem though so cant help with much info

I would avoid mega or alot of benchmarking with ssds though as its pretty unhealthy from the last time i checked. which was not very long ago.

I haven't done a single benchmark involving my SSD/HDD. I am aware of the SSD performance deterioration with benchmarks :-/
Please let me know if priming the system also utilises the SSD?!

 

[R0B_]

Hhhmmm... I wonder if running your CPU and RAM together at those speeds is too unstable?

I will test my RAM once I've got my new RAM cooler through the post dude and let you know how it goes running at 2133MHz... The only difference is that I'm not going to OC my CPU with the ALC 240 just yet... It's a good cooler, but it is set up sucking hot air from inside the case and passing it out over the radiator and out. Once If fixed 2 new 120mm (3000RPM) fans on the radiator to assist with push/pull, then I may go for it.

Why not save up a good bit of cash and invest in a full water cooling kit? Bit of a challenge to set-up, but with some well place radiators it will keep everything chilly... It may also solve any instability problems if it's down to heat.

 

[samx300]

Hhhmmm... I wonder if running your CPU and RAM together at those speeds is too unstable?

I will test my RAM once I've got my new RAM cooler through the post dude and let you know how it goes running at 2133MHz... The only difference is that I'm not going to OC my CPU with the ALC 240 just yet... It's a good cooler, but it is set up sucking hot air from inside the case and passing it out over the radiator and out. Once If fixed 2 new 120mm (3000RPM) fans on the radiator to assist with push/pull, then I may go for it.

Why not save up a good bit of cash and invest in a full water cooling kit? Bit of a challenge to set-up, but with some well place radiators it will keep everything chilly... It may also solve any instability problems if it's down to heat.

Hey R0B_,
Having spoken with PCS support, I do believe that the CPU and RAM are tested when running at such high frequencies. Good decision to improve the airflow for the rad on your C240 I'm sure it'll help. I am also going to attach 2 x Akasa Apache's to my ECO ALC in a Push/Pull config for better thermal management.

I have already spent £2600+ on this rig (entirely) and I want it to work with what I've put in it. If I do go 'all out' on a custom water cooling solution (from EK), it will be because I want to, not because my system can't handle the ECO ALC Plus, I don't think the issues I am having are because of toasty temps

Cheers

 

[R0B_]

Well... I've done some checking this morning and below you can see what information I've gathered...

No issues with testing at all.

I'm concerned that my RAM might not be overclocked like I thought it was... Will investigate more in the BIOS and get back to you!

 

[samx300]

Well... I've done some checking this morning and below you can see what information I've gathered...

No issues with testing at all.

I'm concerned that my RAM might not be overclocked like I thought it was... Will investigate more in the BIOS and get back to you!

+REP for running the tests and confirming your RAM settings mate (plus the screenies).
From the looks of it, your RAM is set up correctly. This can be confirmed via the AIDA64 screeny and also if you go the Memory Tab in CPU Z. I also notice that you are on the precise settings recommended by Kingston - 9-11-9-27 @ 2T

I am also using the same settings for my T1. Bear in mind that if you exceed these, you will not be covered by warranty.

PCS got back to me today and apologised for not setting up my RAM correctly. Its okay as long as I have my system running without any crashes or BSODs. In any case, I don't stress my system during gaming, as much as P95 does during priming

 

[R0B_]

Awesome... Glad to hear it...

I was just about to load screenshots of the BIOS as well. Everything looks like it's checked out there.

Good luck with your Rig mate. Happy gaming!!!