Radeon RX 5700 xt power overloaded my Z420 with 600W PSU.

[Khalifa_alhamdi]

Hi DGroves,

I have already seen the video from greenpcgamers yesterday and was about to order an evga supernova 850W power supply. However, i though i will try the 6 pin to dual 8-pin connector mentioned by Brian and see how it works.

Regarding overloading single rail, please note that i was using the G1 + Molex to power this GFX card. So if the G1 is capable of 216W and was actually delivering 150W through the 8 pin (6pin to 8-pin), then possible the molex was overloaded. However, assuming the card wanted to run at max power of 300W (75W from the pcie, 150 form the G1 and that leaves 75W for the molex connector). Can the molex be overloaded with a 75W output?

Regards,

Khalifa

[Khalifa_alhamdi]

Brian,

Many Many thanks. The 6-pin to dual 8-pin adapter arrived today and the rx 5700 xt  is working great with my Z420 . No power load issue. 

[Brian1965]

Glad to hear the RX 5700 xt card is running well. Once you've had a chance to thoroughly test the card, I would be grateful if you would mark this issue/problem as solved for the benefit of other forum users. 

[Khalifa_alhamdi]

I have marked the 6 pin to dual 8 pin as a solution for this specific machine. 

However, after a few hours of testing, the machine crashed a few times. Restarted.

This happens when i open furmark for gpu test. after some time the machine will go down. 

As well, when i try to run prime95 torture test, i dont get full 100% utilization of all cores and the utilisation goes up and down. Previously, i get 100% at all cores. I think this is related to the high power consumption from the GPU.

In conclusion, the RX 5700 XT does not seem to be a good fit for the Z420. Will try it in the Z820 and see if it will hold.

Regards,Khalifa

[Khalifa_alhamdi]

Good News.

I put my RX 5700 XT on a Z820 with both 6-pin connectors feeding the graphics card (Through 6-pin to 8-pin connectors) and it works just fine. Actually, i run FurMark torture test and Prime95 cpu torture test together for an hour and the Z820 is stable.

In the Z420, runnning furmark alone for sometime crashes the Z420. If I ever try to start prime95 test while the furmark is running, i get an immediate crash in the Z420.

Note, the Z820 has 4 (4-8TB) HDD installed as well. No surprise as the PSU is 1125W here. 

My only issue with the Z820 and RX 5700 XT is that it takes long time for POST. I.e. a few mintues. Normally the Z820 takes longer time for the RAID card to do the checks, but it takes much longer here. Sometimes, after attempting to start i never get video. However, this is fixed if i pull the power cord and try again after say 5 minutes. 

This machine i dont normally shut down, so not a big deal at this point.

regards

[Brian1965]

Sorry to hear about the GPU stability issues. Ironically, it doesn't fit with the arithmetic, e.g. G1 = 12v x 18A = 216W so drawing 150W should only require 12.5A? Possible reasons for this;

1. A more expensive but higher quality 6-pin to dual 8-pin auxiliary PCIe power cable may work. HP does supply their own official 6-pin adapter for this purpose, and has been tested to work in HP workstations where required/recommended. Generic, lower cost 6-pin to dual 8-pin auxiliary PCIe power cables vary considerably in quality, some using very low gauge wire, (SWG = higher is better). Another issue is the connectors and crimps are of a cheaper quality - a major cause of power loss in circuits. The high quality HP adapter cable may allow the RX 5700 xt to run stable under load in your Z420. 

2. AMD GPU cards have quite a bad reputation for drastically under rating the true peak power requirements of their GPU's. Have a look at the Tom's Hardware site; https://www.tomshardware.com/uk/reviews/amd-radeon-rx_5700-rx_5700_xt,6216-5.html  

Although the average power demand was only 223W during the benchmark test, the power demand peaked at 263W!! That is 38W more than its stated 225W. 

3. It may be possible that the issue is not due to the G1 rail being overloaded, but rather that the maximum system power limit may have been reached. i.e. the total power from all components exceeds 600W. Again, a higher quality 6-pin adapter cable may help reduce the overall system power requirements from the G1 rail, but possibly not enough for the system to remain stable under a prolonged heavy load.