Asus HD7850 Overclock

[talZz]

Hello everyone, this is my first time asking for help here at tom's :]

I recently bought a new PC, here are the specs:

CPU: Intel® Core™ i5-3570K 3.4GHz
Motherboard: Asus P8Z77-V
Memory: G. Skill 2X4GB DDR3 1333
PSU: Corsair TX650
GPU: Asus HD7850 2GB (HD7850-DC2-2GD5-V2)

I decided to overclock the gpu (using Asus GPU Tweak).. and i have some questions. but first here is what i achieved:

Stock:
GPU clock: 860MHz
Memory clock: 1200MHz
Voltage: 1.210mV

OC:
GPU clock: 1100MHz
Memory clock: 1450MHz
Voltage: 1.210mV
Power Target: 100 (untouched)
Temp idle: 38c
Temp Max (Full Load): 65c
Fan: Auto

1. Is the stock voltage of my card normal? I ask this because I read this forum alot and from what I read, stock voltages of GPUs are normally lower.
2. Is it a good overclock? I checked my card's ASIC quality using GPU-Z: 70.0% - I tried to go higher than 1100MHz, but even at 1125Mhz it crashed after 10 mins playing Crysis. I didn't try to go higher than 1450MHz for the memory, should I?
3. I assume i can get a better OC if i'll use higher voltage, but this is my first time overclocking and i'm worried i might damage my card. is going up to 1.250/1.300mV ok? I plan on a 24/7 OC.

I'll be very thankfull for any answers.
If there is any info needed, tell me and i'll provide.. any tips for my GPU OC or my system in general would be great!

 

[rene13cross]

First of all, I would recommend using MSI Afterburner instead. I know ASUS GPU Tweak is meant to be pretty good but I found that sometimes it reports clocks incorrectly (such as when applying OCs on startup it wouldn't show the OCed clocks in the actual program making everything really confusing).

1. The stock voltage is pretty high TBH but nothing to worry about as long as your temps are OK. You can even overvolt and OC further as long as your temps stay reasonable. My 7950s are the BOOST version and their stock voltages are 1.25V(!) and I cant even seem to change them. Temps are still amazing though, even when I OC pretty heavily.

2. Yes, that's a great OC for a 7850. And as I said already, you can push it further if you like, as long as temps are good and no artifacting occurs (both core and memory clocks). Artifacting is usually a sign that the memory clock is too high. Crashes are usually a sign that the core clock is too high. (Obviously there are exceptions to that.)

3. As already stated, you can push the card further (including voltages) as long as temps are OK.

If you have any more questions, fire away.

 

[talZz]

Thanks for the quick reply!

You are right about Asus GPU Tweak not applying the OC on startup. I will try MSI Afterburner - is there anything I should know about this software before I use it?
-Edit: Unfortunately, MSI Afterburner doesn't support my card, i can't overvoltage with this software. back to GPU Tweak i guess.

What are the max reasonable temps for my card? are my current temps OK?

I didn't notice any artifacts with this OC - I ran 3DMark11 and Heaven DX11 Benchmark 3.0 several times each + played a couple of hours of Crysis, Crysis 2, Metro 2033, Witcher 2.. so far no artifacts whatsoever. I assume this means my OC is stable?

Can changing the Power Target help OC further without overvolting?

Again, thanks for the quick answers! :]

 

[rene13cross]

Thanks for the quick reply!

You are right about Asus GPU Tweak not applying the OC on startup. I will try MSI Afterburner - is there anything I should know about this software before I use it?
-Edit: Unfortunately, MSI Afterburner doesn't support my card, i can't overvoltage with this software. back to GPU Tweak i guess.

What are the max reasonable temps for my card? are my current temps OK?

I didn't notice any artifacts with this OC - I ran 3DMark11 and Heaven DX11 Benchmark 3.0 several times each + played a couple of hours of Crysis, Crysis 2, Metro 2033, Witcher 2.. so far no artifacts whatsoever. I assume this means my OC is stable?

Can changing the Power Target help OC further without overvolting?

Again, thanks for the quick answers! :]

Apologies for the late response.

Your card should definitely be supported by MSI Afterburner, make sure you try the very latest version (v2.30 AFAIK). It's worth a shot because I found it to be much better than Asus GPU Tweak. The basics are the same across both programs so there's nothing else to know really.

Well, technically the max temp for the card is ~100C but you should never be anywhere near that as it can seriously impair the longevity of the card and also causes instability. My personal max is 80C (for a single GPU config it would be around 75C). Anything under that and your perfectly fine.

Changing the power target has a big effect on performance. Since you have a very good PSU you should put this slider up to the max when OCing as it doesn't involve any voltage changes but prevents the card from throttling clocks when under load (it does this in order to stay within it's TDP). There might be some load temps impact but it should be relatively minimal.

Your card definitely has more potential if you hadn't even increased the Power Target yet!

You can keep pushing the card (Voltages aswell) as long as you stay within the comfortable temperature range stated above.

 

[talZz]

Apologies for the late response.

Your card should definitely be supported by MSI Afterburner, make sure you try the very latest version (v2.30 AFAIK). It's worth a shot because I found it to be much better than Asus GPU Tweak. The basics are the same across both programs so there's nothing else to know really.

Well, technically the max temp for the card is ~100C but you should never be anywhere near that as it can seriously impair the longevity of the card and also causes instability. My personal max is 80C (for a single GPU config it would be around 75C). Anything under that and your perfectly fine.

Changing the power target has a big effect on performance. Since you have a very good PSU you should put this slider up to the max when OCing as it doesn't involve any voltage changes but prevents the card from throttling clocks when under load (it does this in order to stay within it's TDP). There might be some load temps impact but it should be relatively minimal.

Your card definitely has more potential if you hadn't even increased the Power Target yet!

You can keep pushing the card (Voltages aswell) as long as you stay within the comfortable temperature range stated above.

Thanks for the response! :]

About MSI Afterburner - i thought so too, and i tried everything, but i can't seem to control the voltage.. also the core oc limit is 1120MHz. =\

I will try to OC my card further with 20% Power using GPU Tweak later, i hope i can get more out of it!

Right now im at 1100MHz core and 1350MHz memory stable on stock voltage (1.210mV), and i was thinking.. for this OC, i can just use CCC Overdrive, right? considering i don't need to change my card's voltage of course. CCC Overdrive does a good job applying the OC on start-up (GPU Tweak DOES NOT), so is there any reason i shouldn't use it instead, for this specific OC?

I was also wondering - will my Corsair TX650 PSU be enough to power HD7850 Crossfire? What about Crossfire with OC on both? again, my system specs are:

CPU: Intel® Core™ i5-3570K 3.4GHz
Motherboard: Asus P8Z77-V
Memory: G. Skill 2X4GB DDR3 1333
PSU: Corsair TX650
GPU: Asus HD7850 2GB (HD7850-DC2-2GD5-V2)

Thank you in advance :]

 

[talZz]

If anyone can help me and answer these questions, i'll be very thankful :]

 

[talZz]

Best answer selected by talZz.