EVGA GTX 970 - only 2 of 3 heat pipes in use

[Jesse_V]

Apparently there's been some reports of the EVGA Nvidia GTX 970 regarding the finding that only two of the three heat dissipation pipes actually make contact with the GPU. Some people are claiming that this is a cost-cutting cheap move, others are saying that it will make a difference for heat dissipation, while still others think it really doesn't matter.

LinusTechTips covered the topic in his WAN Show yesterday, basically saying that he didn't think it actually made a difference to heat dissipation, and that the card runs pretty cold anyway. You can listen to his comments on https://www.youtube.com/watch?v=g2ccd8ZefNM at the 0:30:32 mark. Personally I agree with him, so I don't think it should make a difference for GPGPU work like F@h IMO.

[artoar_11]

ASUS Strix GeForce GTX 970 DirectCU II OC 4GB Review

Two 92mm downdraft fans operate on top of the heatsink. As the card's shroud does not keep things sealed, most of the resultant hot air will be exhausted into your chassis, so be sure of adequate ventilation. Like the MSI card, the two fans also have the ability to operate semi-passively, and won't spin up until the GPU reaches about 65°C. This is enough of a threshold to enable users to play less demanding games entirely passively. Aside from the obvious noise benefits, this will also increase the lifespan of the card as well as its power efficiency.

EVGA GeForce GTX 970 SC ACX2 4GB Review

Regarding fan noise, we understand that some have expressed concerns over the fan noise on the EVGA GTX 970 cards, this is not a fan noise issue but it is more of an aggressive fan curve set by the default BIOS. The fan curve can be easily adjusted in EVGA PrecisionX or any other overclocking software. Regardless, we have heard the concerns and will provide a BIOS update to reduce the fan noise during idle.

MSI GeForce GTX 970 Gaming 4G 4GB Review

Two 100mm downdraft Torx fans provide airflow, with MSI boasting their new fan design offers 19 percent better airflow and five percent less noise (at 100 percent fan speed). The fan blades alternate between traditional blades that direct airflow to the heatsink, and dispersion blades with a small ridge in them that draw in more air and push it into the path of the normal blades blades, essentially accelerating the airflow. The fans are also wider than the fin stack, ensuring airflow covers the whole card and more.

Performance Analysis

What may be a distraction, however, is noise from the power circuitry. As we said, EVGA doesn't use any upgraded components for its power phases, whereas ASUS and MSI both use higher end parts. It also has only four power phases for the GPU compared to six in the other two cards, which puts more strain and load on the invidiual elements of each phse. The result, sadly, is a relatively low volume but still irritating buzzing noise every time the card is put under load (i.e. when gaming). In a quiet case positioned on the floor, or when using headphones, it won't bother you, but if your case is next to you on your desk then that may not be the case. No power noise was heard from the ASUS or MSI cards.

From here: http://www.bit-tech.net/hardware/graphi ... 0-review/2

[Jesse_V]

Fascinating. Thanks for the illustrative images!

[artoar_11]

See a photo here - EVGA Respond to Possible Design Flaw on GTX 970 ACX

Smaller diameter copper pipe is open at the end. Ie this is not a heat pipe.

[bruce]

Smaller diameter copper pipe is open at the end. Ie this is not a heat pipe.

So what is it? Just a support?

[mdk777]

Smaller diameter copper pipe is open at the end. Ie this is not a heat pipe

Yeah, not certain by a long shot.

Not all finishes on heat pipes need to end in a bullet point. They can be inverted or flush...just depends on the requirement and design.