R9 290X Overclocking: what are "safe" voltages?

[Galatian]

Hello everybody,

I upgrade my computer in December to include two R9 290X in Crossfire watercooled. I already applied a small overclock using MSI Afterburner, but this was all on standard voltage. To further increase my overclock I would like to know what voltages are save to apply? How high do you usually get with the GPU clock?

 

[lavaheadache]

The word you are looking for is "safe" not "save". As far as what is safe, you are going to get very different answers as there are many variables to consider like cooler type and case airflow.

 

[Techhog]

Never listen to others on what safe voltages and overclocks are. You WILL regret it.

 

[KaRLiToS]

Safe voltage is a matter of opinion. It mostly depends of the type of cooling you have.
Since you are watercooled, you have more room to overvolt.

• AIR: 1.3v
• WATER: 1.4 - 1.45v ishh

I also have 290x under water and I have put 1.6v for benchmarking purpose into my cards. I was using pt1 BIOS.
http://kingpincooling.com/forum/showthread.php?t=2473
This BIOS let you use up to 2.0v via GPUTweak. I don't recommend over 1.55v though with a good watercooling system. And only for short period such as benchmark runs. LN2 cooling can take more than 1.6v for sure.

Pt1: Has Voltage drop, meaning that if you set the voltage at 1.4v, under load it will drop to around 1.36v
Pt3: No Vdrop, so at 1.4v, it might give you 1.42v under load.

I prefer pt1.

But for gaming purpose, you are better with stock BIOS and MSI afterburner or Trixx. MSI afterburner will only let you add +100mv but Sapphire Trixx will let you put +200mv.

+100mv could possibly get you to

• Core: ~1150mhz
• Memory: ~1450mhz

+200mv could possibly get you to

• Core: 1250mhz
• Memory: 1550mhz

Those result can widely vary, depends on everycards. "Silicon lottery". It is just a guestimate based on personnal experience.

 

[Faljukin]

I've had poor results with afterburner and amd cards in the past but trixx works great.
Maxing voltage with trixx should be safe with watercooling.

I use +50mv to get 1100mhz for 24/7 use, but can go over 1250mhz with +200mv.

 

[Sunaiac]

Running mine at 1150/1400/+100mv, PT1.
After, the power consumption increase in regards to added performances is bad.

 

[thilanliyan]

I would watch VRM temps closely at anything above stock voltage. They can be hard to cool.

 

[3DVagabond]

If well cooled 1.35v should be fine for even everyday. Thing to watch though is diminishing returns. If, for example, you get an extra 50Hz for an extra 100mv, is it worth it type of thing.

As someone else pointed out watch VRM temps, but they can actually run quite hot and not hurt anything. It's not unusual for cards from both brands to run +100°C even at stock clocks.

 

[thilanliyan]

^Lol, I'm OCD...I keep my VRM temps around 65C (custom cooled)
Isn't stability reduced when VRM temps are high?

 

[KaRLiToS]

My VRMs are at 35-40'c max, with full cover block.

 

[thilanliyan]

My VRMs are at 35-40'c max, with full cover block.

Yep that's the better way of doing it. I use universal blocks though so my vram and VRMs are aircooled.

 

[3DVagabond]

^Lol, I'm OCD...I keep my VRM temps around 65C (custom cooled)
Isn't stability reduced when VRM temps are high?

Nobody is saying that cooler isn't better, but VRM can and typically do run much hotter than that.

This is the hottest stock reference design I've ever seen, but 690's haven't been reported as being unstable or dying early deaths. People even O/C them just fine.

GTX-690