EK’s water block for Asus’s HD7970 DirectCU II has been tested

/ 5 years ago

For those of you who enjoy either EK’s testing reports, or at the same time, the testing to their GTX 680 water block, here’s another read you may appreciate, as the EK team has completed the internal stress testing of their latest EK-FC7970 DCII water block which was engineered specifically for Asus’s design Radeon HD 7970 DirectCU II series graphics cards.

The testing follows the same method as usual, thanks to Niko “tiborrr” Tivadar.

The test has been conducted using the following water cooling components and measuring equipment:

  • EK-FC7970 DCII prototype (RTM) water block
  • EK-RAD CoolStream XT 360
  • 3x Yate Loon D12SH-12 120mm 2200rpm fans
  • 2m 12mm ID tubing (1/2″ ID)
  • D5 Vario water pump + EK-D5 X-TOP V2
  • EK-RES X2 Multioption 250 Advanced
  • EK-12mm High Flow fittings

Measuring equipment:

  • Greisinger GTH 175/Pt J-type thermometer, calibrated
  • Voltcraft IR-800 20D IR thermometer
  • Digmessa digital flow meter FKHU series

Since the DC2(T) series graphics cards are built with overclocking in mind we decided to push our sample in order to stress test our water block’s cooling engine. Furmark torture benchmark which stresses the graphics card to the maximum was ran for more than one hour. Overclocking the graphics card from factory set 1000/1400MHz to 1300/1600MHz (GPU/RAM respectively) with Vgpuvoltage set at 1.25V (1.22V after Vdroop) yielded the following result:

  • Tgpumax = 44°C
  • Th2omax = 33.1°C
  • dTmax = 10.9°C = ~ 11°C

Where Tgpumax is the highest temperature of the GPU core, logged by software; Th2omax is the highest temperature of the coolant measured by thermometer; dTmax is the highest delta (difference) between the GPU core temperature and the coolant temperature – lower is better.

Please note that the smallest resolution for Tgpu probe is 1°C therefore a rounding error is present. Considering this fact we can see that dT does not increase more than a 1°C even at overclocked conditions. The VRM (voltage regulation module) also remains cool, the hottest measured temperature was ~ 54°C (behind the MOSFETs, on the back side of the PCB; 61°C in overclocked mode). Note that ASUS software probe reports VRM temperatures higher VRM temperatures – 56°C in 2D idle mode (non-overclocked state) and 86°C while under full load (overclocked state).

Mounting mechanism also support installation of ASUS original backplate but user can install water block without one as well. EK will also include a 2-slot I/O bracket which will free the adjacent PCI/PCIe expansion slot and ease the installation of multiple graphics cards. Due to the shear size of the printed circuit board the EK-FC7970 DCII water block uses G1/4 ports on acetal top only. The interconnectivity of multiple EK-FC7970 DCII water blocks is ensured via EK-FC Bridge & Link system.

The EK-FC7970 DCII water block again excells in hydraulic performance chart. The design once again features extremely low flow resistance, somewhere in the range of EK-FC7970. As a result any medium performance water pump will run four of these water blocks yet still offer enough flow for optimal system operation. Picture below shows the hydraulic curve:

The EK-FC7970 DCII water block will come in two versions – Copper Acetal for €92.95 and EN Nickel Acetal for € 99.95 – and is already listed in the EK webshop but it will be available for purchase in the weeks following. A matching FC Backplate is also in the works and will be available in the following weeks.

Source: Press Release