Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

[dicky96]

Hi guys
I have this laptop here and it isn't working as expected. It has a built in GTX960 GPU but it does not appear to use it - it only gives 7 FPS in furmark

The GTX960m is visible in Windows and Speccy.
http://speccy.piriform.com/results/W...ZdK3KWSl2xMeIj

At first I though this was some driver issue and opened a thread on bleeping computer. You can read that here.

https://www.bleepingcomputer.com/for...rk-framerates/

In the end it appears to be related to another problem I spotted - which is the following:

I have the laptop connected to my bench power supply because the owner can't find the original one. My bench PSU is 0-30V 0-6A. The original PSU is 19V 6.3A so that's close enough.

When I got the laptop the battery was completely flat so I connected to my PSU, set to 19V and I could see it was drawing 1.7A and the battery was charging but after 20-30 mins the current goes to zero and it won't charge any more.

I can power up the laptop, with my PSU still attached and it will run for about 20 mins until the battery goes flat again (the battery is about 22% charged to start with). After about 20 mins, or less if I am running some benchmark, the laptop reports the battery is low and shuts down.

It then starts drawing 1.7A from the PSU again (for about 20 mins) but the interesting thing is that while it is running from battery it is drawing zero amps from the PSU like it isn't connected to the mains at all.

Now it seems the problems with the GTX960, which is probably related to missing Power Plans in Windows 10, is very likely related to this issue with the power supply and the fact it will only run from battery, which also does not charge fully.

I tried disconnecting the battery and starting the laptop and then it does draw power from the mains. I see the current go up to 2.93A, I get a picture on screen for a second, then I hear a funny little noise from the laptop (like a ping or blip) and it switches off, the current goes back to 0A. I actually see the CC LED on the PSU flick very briefly and the PSU makes a relay click sound.

Any suggestion?

[sikocan]

Re: Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

First thing first. You can’t use benchtop psu as power supply. Get proper charger first.

[sikocan]

Re: Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

Check with gpuz tool to see power usage

[dicky96]

Re: Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

@silkocan - why can't I use the bench PSU?- Is there something special about this laptop? It can supply 19V 6A which is enough, and I never had a problem powering other laptops, or anything else under 30V/6A from it

https://www.youtube.com/watch?v=RMIySInnCxo

I do have another bench supply like the one in that video 1-30V 5A I suppose I could try that if there is some reason for not using the Iso-Tech?

[piernov]

Re: Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

I'd still try a known good compatible AC adapter with correct power rating.

[dicky96]

Re: Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

Yeah the problem there is that power supply (the original type) are very expensive if I can even find one at all. There are compatible (voltage and current) ones but they don't have the weird power connector to fit the laptop

So I tried my other bench PSU which is 30V 5A and it seems to like this one more. I get the same thing, the battery charges for about 25 mins, then the charge current goes to 0A (actually it flicks between 1.6A and 0A every few seconds)

After the battery has "charged" if I power up the laptop it draws about 4.7A from my PSU, then the current goes all over the place - 0A to 3.5A and I am getting an icon on screen which is flicking between battery and power adapter, the screen brightness also goes up when it switches to power adapter, but afte a second it goes to battery again. I can see the CC LED on my PSU flicking even though the 19V is stable

I guess I really should have bought the 10A bench PSU when i had chance lol

I will tell the owner he needs to find the original charger. Unless someone knows where I can get the correct coaxial connector and solder it to a compatible 120W charger.

Problem is I still don't really know if there is some other fault on the laptop - it seems odd the battery only charges to about 25% as both my bench PSU are happy to supply the 1.7A charging current

[piernov]

Re: Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

If the battery still doesn't charge fully with the correct AC adapter then most likely the battery is dead as usual.

There's a reason why https://www.badcaps.net/forum/showthread.php?t=88758 says

Always make sure the correct AC adapter was used with the machine. Genuine original AC adapter of the correct brand and correct power rating. Even if the connector is correct, it doesn't mean it will work and it can even damage the machine.
Battery-related issues are 99% of the time the battery itself. Even if the battery is new. There are so many garbage batteries on the market that you sometimes get 2 or even 3 bad batteries in a row. This is especially true for Apple machines.

I've seen too many people wasting time, risking boards, even damaging them just because they didn't have a good AC adapter/battery.

[dicky96]

Re: Asus ROG Laptop G771J - GPU very low frame rates and PSU problem

The owner is getting a PSU for the laptop