Screen Flickering

[d1nky]

all the vrms are cooled passively which they should only touch the baseplate, its a huge piece of metal which should cool good enough.

well it does on mine, vrms never go above 60-65*c even overclocked.

im starting to wonder if its all a sensor issue, or everything is related and its not being cooled properly!

try take some pics of the base plate, i may open mine up again to compare.

not tonight, its late maybe tomorrow or something

 

[Tintai]

*Update
Diode 73C
VRM1 104C but grows very slowly.

Good idea. Maybe it's something wrong with sensors. Tomorrow I take pics.

@edit:
I have a flickering but smaller and less.

 

[Law-II]

Hi

Looking at the PIC posted in #64

-Assuming the card had been squeezed together to check the pressure from the fansink baseplate, there seems to be two areas that are not in good contact [this may indicate either; uneven pressure to that area; bowed or warped PCB or bowed or warped fansink baseplate]
Example: here

The area in the middle is how it should look, all the way along the grey strip of thermal pad; where pressure can be seen clearly.

Note: to rule this out either place indervidual pads or strips of three across the VRM's and use a combination of 1.0mm and 0.5mm thermal pad toward the edges to compensate for poor contact.

atb

Law-II

 

[Tintai]

So I must add some pads in this area? I look again.

Red is RAM and have all pads.
Yellow is VRM1(core - sure?) and have a one big pad.
Green is VRM2(memory) and have any pad. When I close baseplate I can't see any radiator on greens chips. It's normal?

Also I can use external sensor. But not now. I must borrow it.

 

[itsakjt]

Yes make sure all the memory chips and VRM MOSFETs have the pads and make sure they all come in contact with the heatsink. And you don't need to cool down the chokes. They are designed to withstand VERY HIGH temperatures. So you don't have to cool those silver rectangular things inside the green boxes.

 

[Law-II]

Hi

Red is RAM and have all pads.

Yes

Yellow is VRM1(core - sure?) and have a one big pad.

As mentioned there dose not look to be good contact toward the edges of this thermal pad when looking at the middle of the pad you can clearly see good contact as the impression of the VRM's can be seen; however toward the edges of the thermal pad looks smooth with little to know distortion in the pad.

Green is VRM2(memory) and have any pad. When I close baseplate I can't see any radiator on greens chips. It's normal?

This example shows where chips do not touch the Fansink Baseplate; thus do not require thermal pads as these components are air cooled

Source - here

+1 Dinky; when running the card ensure that the fans are enabled as manual in the catalyst control center; run them at 100% when testing

atb

Law-II

 

[d1nky]

you really should research driver mosfets, theyre the lil black squares with legs out. they control the pwm of voltage and get hot!

this is an excellent read with basically the same principles http://www.hardwaresecrets.com/prin...The-Motherboard-Voltage-Regulator-Circuit/616

i said before that the vrm pad across the strip of mosfets didnt look right. vrm1

mine are sat firmly in the pad, and pad adjoins both baseplate and vrm nicely!

i do think that your screen flickering may be a cause of the vrm temp. temps too high = poor voltage control and lots of ripple = corrupted/degraded chip

or it could be unrelated, im not a pro lol


itsakjt, pointed out the choke. it doesnt need cooling, but the mosfets do. read the above article

 

[Tintai]

Ok, so today I will try to press this VRMs to heatstick.
Thanks.

@edit:
No, it's no possible.

I add 0,5mm pads and temperature is the same.

Removed

So I don't now. Maybe it's sensor issue, not real temperatures.

 

[The Mac]

Looks like thiere is way too much thermal paste on the GPU....

 

[d1nky]

WTF have you done with that gpu core! LOL

i would stop messing before you truly break it!

bent pcb, dirty dollop of shit on the core, the pads should be narrowish strips that compress when fitted. you want to make heat transfer not insulate the fuckers!

i hope that isnt conductive paste!

 

[itsakjt]

WTF have you done with that gpu core! LOL

i would stop messing before you truly break it!

bent pcb, dirty dollop of shit on the core, the pads should be narrowish strips that compress when fitted. you want to make heat transfer not insulate the fuckers!

i hope that isnt conductive paste!

Well if it is conductive, then I bid adieu to the GPU if it was powered on.

 

[d1nky]

Well if it is conductive, then I bid adieu to the GPU if it was powered on.

its like he was doing it outside and a bird..........

 

[Tintai]

i hope that isnt conductive paste!

Of course not. It's non-conductive.

Maybe a little too much but nothing bad will happen.

And I can't add more pads to this VRMs. Everything is fit, but the temperature is still the same.
I removed this additional pads, bcs I afraid about PCB.

 

[The Mac]

um yes, too much paste will act like an insulator and raise your temps.

there should be a small amount the size of a pea placed in the center of the chip, and it will spread when you replace the heatsink.

What you have there is aweful.

Thermal paste is designed to fill in the imperfections of the surfaces to maximize direct metal contact between the heat spreader on the core, and the heat sink.

It is not designed to be the filling on the inside of an Oreo.

lol

 

[itsakjt]

its like he was doing it outside and a bird..........

LOL No thermal paste should touch the SMD capacitors. All insulators are bad conductors. But they ARE conductors.

 

[d1nky]

1. you cant add pad on pad, the heat transfer will be terrible
2. they should be narrow strips, covering the driver mosfets that are in a row of pairs.
3. i would remove that pic of the paste before people think you are on crack lol
4. try straighten the pcb, you may jeopardise core contact.
5. clean the core caps with a toothbrush and tim cleaner
6. a dab of non conductive paste on the vrm and opposing side of heat pad may help
7. sell me the card lol

 

[Tintai]

Yea, I fix this. Give mi five minutes.
PCB is no permanently bent.

 

[The Mac]

3. too late

lol

 

[Frick]

There's a bit flex in PCB's. I doubt that would break anything, if it's a healthy card.

 

[d1nky]

even the paste on this is too much. but the vrms pads are quite thick, like mine!

and did your card actually have the vrm thermal pad to begin with??


im just thinking, when i had some shitty psu. my vrm temps/core temps/ mobo temps were a lot higher than a decent psu.

something about poor ripple supression and 'dirty' power. just a thought!

 

[The Mac]

that and insufficient power from the PSU would make the VRMs work harder to maintain stable power.

 

[d1nky]

what would an asus 7970 draw in terms of power and amperage?

 

[Tintai]

Ok I fix this paste.

But... Somethimes I have even 20A on VRM. What the hell? Maybe it's sensors issue.
Now I have 0.25A to max 5A.

@edit: In English.

And now I take screen when it's 20A...

PSU: OCZ ZT 650W

 

[d1nky]

amp * volts = watts

seems normal i think. and the amperage will change on power draw

 

[The Mac]

20A isnt so unusual at full load.

dont forget its not 110v, so its not like you are drawing 20A at the wall...

my system at full tilt with a 7970 OC eddition, and a sandy i5-2500k clocked to 4.5ghz draws a little less than 300W at the wall.