4790K high temps Custom Loop
4790K high temps Custom Loop
I'm using a 4790K on a Z97 Sabertooth board. I recently added another 980Ti to my computer/loop. When checking temperatures, the CPU was hovering in the upper 60s to low 70s with minimal load (Windows Media Player Classic and Chrome 5 open). I haven't revisited the overclocking settings since originally, just changing the multiplier to 46 per day. Running Prime95 caused it to jump to 99c, so I turned it off immediately. I suspected there might be bubbles in the loop, so I temporarily underclocked and undervolted for a week, double-checked connections, and reapplied thermal paste to the CPU block. After setting everything to auto, the temperature rose back to 99c. This time I focused on core temperature, which showed a reading of 1.383. I attempted to lower it via BIOS adjustments and adaptive voltage, but it still failed to boot at anything above -0.4 with a turbo adjustment of 0.25. At those settings, while the immediate temperature improved, it remained in the high 80s to low 90s. My loop includes an EVGA 980Ti with an EK full cover, an Asus Strix with an EK full cover. On my processor, it's a 4790K with a Supremacy MX. The loop runs through pump-CPU-EVGA-Strix-420Rad-reservoir-pump. My case is a modified Enthoo Pro window. I have two ippc 3000 fans on the bottom intake, two more on the front, one mounted to the pump (EK D5 PWM), a Phanteks fan in the back that came with the case, and three ippc 3000 fans on the radiator to push air out. I've spent about three hours tweaking settings, but no matter what I do to bring temperatures down to the desired levels, it still doesn't boot. Additionally, both video cards are BIOS-configured for 425 watts and reach a max of 48c under load. I believe this is mainly due to the 64C processor contributing slightly more heat. The room temperature is around 29°C, with idle temps around 33–35°C. Any advice would be greatly appreciated. Thank you for reading.
I believe a 7-8C reduction is quite notable, particularly under load.
In the future, consider dividing your post into smaller sections. Long blocks of text are hard to read. Lists help clearly display your components. Also, VID is not the actual voltage; it's Intel's estimate of your vcore at a specific frequency. At your 46x multiplier (for example, is that 4.6 GHz?), what vcore were you using?
If you have a 420 rad, why are there only three fans running?
Can you observe the effects if you run your pump at maximum instead of PWM?
The 420 radiator measures 3X140mm, which means the maximum I can fit in push configuration is three. The 46 multiplier runs at 4.6Ghz with a base clock of 100Mhz; this isn't about bragging—it's just an everyday overclock. Baseclock overclocks on Haswell can sometimes be inconsistent. I understand VID isn't the same as the core temperature, but the coretemp program is well-known. Someone more experienced might help clarify my position.
CoreTemp provides detailed information and additional insights, revealing your vcore accurately.
Can I enable a fixed voltage setting? That would likely be ideal for current troubleshooting.
Installed HWInfo once more, but it displays the VID instead of the VCore, although it does show a static V number that doesn’t indicate the processor’s activity. Then there is this.
"This scenario applies to nearly all CPUs before Haswell (the fourth generation Core line). After Haswell and beyond, these chips include a Fully Integrated Voltage Regulator (FIVR) that receives a steady ~1.8V and then controls the required voltages for each rail inside the CPU. On these models, checking Vcore can be challenging since it’s built into the chip, but some motherboards are able to handle this (though I’m not certain about their exact methods or accuracy)."
http://www.hwinfo.com/forum/Thread-Quest...-and-Vcore
HWinfo provides similar data as CoreTemp regarding the processor, but it doesn’t help much for troubleshooting.
I also have a fixed voltage option; at 1.25 volts it tends to be unstable and generate heat, whereas in the past I achieved stability around 1.18v at 4.8GHz under 80°C."
I found a vcore listing, currently priced at 1.36, but I'm still facing the same issue. When I attempt to reduce the price without adjusting the multiplier, the system won't start.
The only thing that comes to mind is that your processor has overheated slightly and requires higher voltage than before.
The initial details suggest a high delta, but later you mention idle temperatures around 60-70°C and then a cooler 33-35°C. Which is accurate depends on clarifying the context or calculations.
Regarding your delta-T question, you're using an 88 watt CPU with overclocking, and BIOS-modded 980 Ti's at 425 watts. This implies a significant power draw, possibly exceeding 900 watts under full load with three fans. Your estimates of 15+°C TDP seem reasonable given the setup.