The CPU Hyperthread does not operate properly when using Prime95.
The CPU Hyperthread does not operate properly when using Prime95.
Hey everyone,
I wanted to share some thoughts and get your feedback. I recently installed a new system and have been facing stability problems. I think I might have missed out on something important. Here’s what I have set up:
CPU - Intel i7-8700k
Motherboard - MSI Gaming M5 Z370
RAM - Corsair Vengeance LPX DDR4-3000 (2x16GB)
GPU - EVGA GTX 1080 Ti FTW3 Elite Gaming
Power Supply - EVGA Supernova NEXG 750W 80+ Gold
Cooler - Thermaltake Floe Riing 360 AIO
SSD - Samsung 960 M.2
Initially, I managed to get it running smoothly at around 4.8GHz with a -2 AVX offset. However, at 1.3v (which seems quite low), stability dropped significantly. RealBench won’t pass without the system crashing during the test. I ran Memtest for over two hours without any errors, so I’m confident the RAM isn’t the issue.
Occasionally, when launching Prime95 v29.3 with Core#2 and Thread#1, the process stalls but doesn’t complete anything meaningful. HWINFO64 shows the core is only at 50% utilization. The only solution seems to be rebooting the machine.
I’m wondering if this points to a processor problem, an issue with Prime95 itself, a Windows configuration hiccup, or a motherboard fault. Any suggestions would be greatly appreciated. Also, since I’m still new to overclocking, I’d love some guidance on that too.
Additionally, during Prime95 runs, CPU temperatures reach around 90°C—hot but not dangerous, though it triggers VR Thermal Throttling when power delivery hits 115°C. Why is that happening?
Thanks in advance for your help!
I believe what you're doing by moving the fans to the top is essentially the same as before. Using the rear case fan and rear vents helps push out hot air from the case, allowing better airflow over the Mobo parts. Adding a small fan to the VRM heatsinks would probably be beneficial. Check this thread for more insight: http://www.overclock.net/t/1476618/water...t_22020875. Regarding the 29.3 prime, do you need to stress with AVX instructions? If not, testing with 26.6 would be a better option since it doesn't require AVX. http://www.mersenneforum.org/showthread.php?t=15504. Also, are any voltages set to auto or is XMP enabled? The biggest change was swapping the fans from exhaust to intake...
Which case are you employing, and what is the number of fans along with their setup?
biglizard :
case air flow?
what case are you using? what are the fan numbers and setup?
i have two 140mm fans at the front, running at full speed, and one 140mm fan in the back on PWM. the radiator is mounted on top with three 120mm fans. i'm using a thermaltake v51 core.
Drakke114 :
Case airflow situation?
Which case are you using? What fans are you employing and their settings?
I’m using two 140mm fans at the front, running them at full speed, and one 140mm fan in the back controlled by PWM. The radiator is mounted on top of the case with three 120mm fans. The case model is a Thermaltake V51 Core.
If the VRMs are getting hot, the CPU won’t last.
I believe this could be the root cause, or at least part of it.
One issue with water cooling is reduced airflow over the VRM areas that traditional coolers provide.
Plus, an AIO takes up most of the air coming from the front intakes and restricts air reaching the motherboard’s components. Adding a small fan blowing directly on the VRMs might help temporarily, but improving case airflow is essential.
Consider raising the rear fan curve.
Drive cages aren’t assisting if they’re in place.
I’d like air to flow from front to back. If possible, mount the AIO in front of the case and close the top vents.
I have one cage at the bottom for another SSD and a 2TB HDD. Would adding fans at the bottom help at all? I can't move the AIO in the front because of that drive cage. If I don't run P95, the VRM temperature stays around 60°C during gaming, etc.
I also found out that I could mount other hard drives on the back, freeing up space at the front for the rad. Still, would it be better to shift the two fans from the front to the top and use them as extra intake instead of closing the top?
biglizard :
drakke114 :
Case airflow situation?
Which case are you using? What fans are you employing and their settings?
I’m using two 140mm fans at the front of the case running at full speed, plus one 140mm fan in the rear operating on PWM. The radiator is mounted on top with three 120mm fans. The case model is a Thermaltake V51 Core.
If the VRMs are getting hot, the CPU won’t last much longer.
This seems to be the issue, at least partially.
One of the challenges with water cooling is reduced airflow over the VRM areas that traditional coolers provide.
Plus, an AIO takes up most of the air coming from the front intakes and restricts air reaching the motherboard’s components. Adding a modest fan blowing directly on the VRMs could help temporarily, but improving overall case airflow would be better.
Consider adjusting the rear fan curve.
Drive cages aren’t doing much, if they’re there at all.
I’d like air to flow from front to back. If possible, mount the AIO in front of the case and close the top vents.
I removed the cages, moved the radiator to the front, and installed the front-mounted fans higher up for better intake. No changes yet, but VR Thermal stopped after 15 minutes.
I need to know the type of case you're using and the number of fans along with their settings. I've got two 140mm fans in front running at full speed and one 140mm fan in the back on PWM. The radiator is mounted on top, and it's a Thermaltake V51 Core. If the VRM gets too hot, the CPU won't last. I believe this could be the issue, or at least part of it. Water cooling can reduce airflow over VRM components, and an AIO usually takes up most of the front air intake, limiting flow to the motherboard. Adding a small fan near the VRM might help, but improving case airflow is important. Consider increasing the rear fan curve. If the drive cages are in place, they may not be helping. I'd prefer air to flow from front to back, and if possible, mount the AIO in front of the case with closed top vents. I removed the cages, moved the radiator to the front, and added fans from the front to the top for better intake. No changes yet, but VR Thermal kicked in after 15 minutes. Looking at a thread might clarify things: http://www.overclock.net/t/1476618/water...t_22020875. Also, check if any voltages are set to auto or if XMP is enabled.
I believe shifting the fans to the top essentially replicates your previous configuration. It seems using the rear case fan and rear vents helps expel heated air from the case, allowing better airflow over Mobo components. Adding a small fan to the VRM heatsinks would probably be beneficial. Check this thread for more insight on case airflow: http://www.overclock.net/t/1476618/water...t_22020875. Regarding prime 29.3, do you need to apply AVX instructions? If not, prime 26.6 would be a better option since it doesn’t require AVX. http://www.mersenneforum.org/showthread.php?t=15504. Are any voltages configured for auto or XMP enabled? The main change was swapping the fans from exhaust to intake, which should improve airflow across the VRMs. My BIOS settings show LLC set to Mode 4.
I believe shifting the fans to the top essentially replicates your previous setup. Using the rear case fan and rear vents to expel hot air from the case should improve airflow over the Mobo parts. Adding a small fan to the VRM heatsinks would also be beneficial. Check out this thread for guidance on case airflow: http://www.overclock.net/t/1476618/water...t_22020875. Regarding prime 29.3, do you need to apply AVX instructions? If not, testing with prime 26.6 would be preferable since it doesn’t require AVX. http://www.mersenneforum.org/showthread.php?t=15504. Are any voltages configured for auto? XMP is enabled. The biggest improvement came from swapping the fans from exhaust to intake, which should push more air across the VRMs. My BIOS settings show LLC in Mode 4. Everything seems fine, though I’m not very experienced with this chip—others might be better at assisting. http://www.overclock.net/t/1639998/i7-87...d-settings