The Radeon 7850 is an overclocking beast

[tuffluck]

i have had my sapphire 7850 since april and have had a lot of time to optimize the OC. i run 12.10 drivers at 1200mhz clock and 1400mhz memory and that has been stable for some time. vcore is set to 1.19v, and i use GPU Tweak. temps get up to 70c when playing BF3, but i have seen no signs of deterioration at those temps. from what i researched beforehand, 70-75c is about the maximum safe temperature for these cards. not sure what specific online information got me to that conclusion, but i remember reading quite a bit about the subject before i was comfortable with it. i leave the fan on stock speeds because of this.

 

[dr.noob]

I went to 1.3v 1270_core with Asus Tweak 2.0.6.0 as the newer versions lock your voltage or limit to certain point like 1.225v.

I5 2400 3.2 + Asus DCU ll 7850 2GB the beast - P7301 - on 3dmark11

http://www.3dmark.com/3dm11/5404707

1.3v furmark and 3dmark11 stable at 1270mhz with the stock cooler, fan 100%.

1.3V furmark stable at 1300mhz



I need to do more testing and tweak it better.The next steps will be adding some small dissipators to the vrm and better thermal grease as this was with the original stuff.

:thumbsup:

 

[tijsva]

Swapped to an arctic xtreme 7970 on my sapphire 7850 which allows me to be 24/7 stable at 1220 core 1325 memory 1225mv. I want to push it by raising the voltage to 1300mv but flashing an asus oc bios results in a non-working 7850.

Any idea's on how to "unlock" my voltage to 1300mv?

 

[skipsneeky2]

You guys are nuts with those overclocks

My msi tf3 7850 was sucky being stuck with 1225mv and not going a inch over 1050 core.

 

[dr.noob]

Swapped to an arctic xtreme 7970 on my sapphire 7850 which allows me to be 24/7 stable at 1220 core 1325 memory 1225mv. I want to push it by raising the voltage to 1300mv but flashing an asus oc bios results in a non-working 7850.

Any idea's on how to "unlock" my voltage to 1300mv?

Try Asus Tweak 2.0.6.0 + CC or Sapphire Trixx.

 

[yepp]

I went to 1.3v 1270_core with Asus Tweak 2.0.6.0 as the newer versions lock your voltage or limit to certain point like 1.225v.

I5 2400 3.2 + Asus DCU ll 7850 2GB the beast - P7301 - on 3dmark11

http://www.3dmark.com/3dm11/5404707

1.3v furmark and 3dmark11 stable at 1270mhz with the stock cooler, fan 100%.

1.3V furmark stable at 1300mhz



I need to do more testing and tweak it better.The next steps will be adding some small dissipators to the vrm and better thermal grease as this was with the original stuff.

:thumbsup:

Impressive OC.

I found Unigine Heaven to be the most sensitive stress test for my 7850.

 

[tijsva]

@dr. noob, asus gpu tweak wont let me adjust voltage (even tho voltage adjustment is checked) trixx maxes out at 1225mv.

I can run furmark, msi kombustor and evga artifact scanner for hours on 1275 core -1350 memory, but this isnt stable in games like black ops 2. 3dmark11 runs fine.

 

[dr.noob]

@dr. noob...

Hello.

My little beasty.










Use 2.0.6.0 version, it's the best, at least for me.

Mine runs at 1.3v but i wanna play safe so the best 24/7 for me is with 1.28v, fan 40% on manual max 60ºC running 3dmark11, i checked with hwmonitor log.

My new best is this(now with ram overclock at maximum):

core: 1250 1.280v

mem:5500

http://www.3dmark.com/3dm11/5437863 with i5 2400 3.2

How to use Asus Tweak 2.0.6.0:

http://support.asus.com/download.aspx?p=9&m=GPU+Tweak&hashedid=n/a

1.start the program, it will take like 10s to start, don't know why, but the latest version 2.2.9.9 it's a lot quicker, though it's more limited;
2.click on the lower left corner where it says advanced mode;
3.go to settings, tuning;
4.mark gpu voltage and overclock range enhancement;
5.now with my asus cu2 v2, normal version(it's not the top one) i can overclock to 1.3v and the maximum core is 1720 and memory 9600.

With this version you can't change the power limit, so in order to do that use CC.

 

[dr.noob]

Part 2 of the images:

Check the power of the tape.

 

[KingFatty]

Nice heatsinks. Did you happen to collect data on the VRM temperatures pre-heatsink application and post-heatsink application, to see what difference the heatsinks made to VRM temps at a given load?

Also, is that white stuff under the heatsink a thermal pad or tape you got separately?

 

[dr.noob]

Nice heatsinks. Did you happen to collect data on the VRM temperatures pre-heatsink application and post-heatsink application, to see what difference the heatsinks made to VRM temps at a given load?

Also, is that white stuff under the heatsink a thermal pad or tape you got separately?

Unfortunately i did not collect any data because i don't have any sensors or material to do the testing.

The white stuff is thermal grease between normal tape.

Does anyone think this is a bad modification and should i replace it with thermal pads?

 

[lavaheadache]

what kind of tape is that?

 

[dr.noob]

what kind of tape is that?

It's normal transparent tape from the office. :thumbsup:

I have the other on the left too, which one is better?Thermal tape or the normal one?Nonetheless i think this one will do the trick.

 

[KingFatty]

Be careful here, you may be causing the VRM heatsinks to act like little "blankets" and allowing the VRMs to actually be warmer than if they were left bare and exposed to direct airflow.

Perhaps take a look if you can get a utility to monitor the VRM temperatures, and then see what your actual temps are (e.g., stock voltage/fan settings) and compare those to other users who have the same card but without the heatsinks.

There are some people with other cards that report an increase in VRM temps when using these kind of heatsinks.

Also, for the tape method you used, I'm not familiar with any data on how it works. However, I worry that the method you use will "squish" or allow migration of the paste over time, reducing effectiveness. Maybe if you could add a clamp or other form of pressure, it might be OK, but then with a clamp you won't need the tape at all. Typically the special-purpose thermal pads/tape will be spongy/expanding to fill this need, and you can buy them in different thicknesses and thermal performance as-needed.

But you should collect heat data and see how things compare to other users and whether your VRM temps are good.

 

[dr.noob]

The heatsinks are from my "old" MK-13, they sure look nice.

You have a point, but i don't think any of the 7850 have internal vrm sensors...

If i collect some data with an external sensor i will add it to the feedback.

I would like to buy the proper vrm cooler for this card because it has 2 points to secure it as you can see.Maybe only the TOP or 7870 has it from the factory.

EDIT: after seeing some reviews none of the cards from the factory have the vrm cooler, meaning they probably made those 2 holes for some aftermarket cooler like the AC.

 

[tijsva]

@dr. noob, that tape is only making them hotter ptobably, the whole point of a heatsink is dispensating the heat from the material it is brought in contact with... since regular tape has no ability to do so, unlike thermaltape or thermalpaste you are now isolating the heat underneath.

Use thermalpaste or 2 component thermalpaste (with glue in it).

 

[dr.noob]

@dr. noob, that tape is only making them hotter ptobably, the whole point of a heatsink is dispensating the heat from the material it is brought in contact with... since regular tape has no ability to do so, unlike thermaltape or thermalpaste you are now isolating the heat underneath.

Use thermalpaste or 2 component thermalpaste (with glue in it).

Thanks for your input, i shall collect some data and compare or remove the tape, the only problem using thermal grease directly on top of the vrms is the mess it may do, and i'm not sure if my paste has conductive particles that may short circuit the vrms.

The glue thing might work, i will eventually give it a shot.

It looks i'm out of thermal grease...damn , i think i'll just buy some thermalpads like i should have done in the whole beginning.

 

[MrHT]

Nice heatsinks. Did you happen to collect data on the VRM temperatures pre-heatsink application and post-heatsink application, to see what difference the heatsinks made to VRM temps at a given load?

Also, is that white stuff under the heatsink a thermal pad or tape you got separately?

Don't leave that is necessary

 

[dr.noob]

In Portugal i can buy the EK Thermal PAD - FC BIG 0,5mm (75x50mm) for $3,9

What do you think?There are 1mm and 1.5mm as well.

And for $4,6 i can have the

AKASA 80x80mm
0,30 mm
Condutividade térmica:
0.9 W/m. °C

Are there other vrms on the pcb that should be cooled also?

 

[tijsva]

I currently have 2 packs of AKASA 80x80mm in front of me. I'm going to use it for the memory as well as for the vrm's. One pack should be sufficiant I think, but 1 is for spare

Does anyone know if the memory can be vmodded as well?

 

[dr.noob]

I have some data, i pulled the heatsinks/tape off and while running Furmark at stock clocks i put my finger on the ram and vrms, guess what, they were hot, especially on the vrm, i could touch it for only 5s.

If anyone is going to overclock these beasts then you should use some heatsinks or buy something like the artic cooling solutions.

http://www.arctic.ac/en/p/assistant/vga/chip/240

The funny part is i did run at 1.3v 1300_core with the fan at 100% and nothing happened. uf(luckly the fan was not auto 10%)

 

[krumme]

club 3d 7850 1G, royal king, 1050MHz on stock voltage. Thats as long as the slider in the catalyst center allowed me to. ROLF. I dont care for more, because it drives the bf3 in ultra without msaa perfectly fine at 1080p and i dont game anyting but bf3.

 

[dr.noob]

club 3d 7850 1G, royal king, 1050MHz on stock voltage. Thats as long as the slider in the catalyst center allowed me to. ROLF. I dont care for more, because it drives the bf3 in ultra without msaa perfectly fine at 1080p and i dont game anyting but bf3.

Try Sapphire Trixx or Asus Tweak 2.0.6.0. :thumbsup:

 

[KingFatty]

I have some data, i pulled the heatsinks/tape off and while running Furmark at stock clocks i put my finger on the ram and vrms, guess what, they were hot, especially on the vrm, i could touch it for only 5s.

If anyone is going to overclock these beasts then you should use some heatsinks or buy something like the artic cooling solutions.

http://www.arctic.ac/en/p/assistant/vga/chip/240

The funny part is i did run at 1.3v 1300_core with the fan at 100% and nothing happened. uf(luckly the fan was not auto 10%)

And I'll add the concern that even though the VRMs give off heat, you have to make sure that your modification is *helping to cool* the VRMs.

There is a possibility that adding a heatsink to a VRM will *trap heat* and cause the VRM to run hotter, especially if your thermal interface is not efficient, and the heatsink causes a deadspot where air doesn't circulate as efficiently.

Just putting a heatsink onto something, especially the tiny VRMs, does *NOT* necessarily mean it will be cooler. You always want to test the before/after temperatures and verify you are improving the situation.

Shame you don't have a temperature monitor for the VRMs, but do you have a temperature probe you can insert under the heatsink right next to the VRM? My voltmeter has a thermocouple like this, and also my fan controller has temp probes made for this purpose, perhaps someone can run a test like this?

I'll be doing it when I eventually upgrade to a new video card, but that's going to be a while and probably not till the next round of new cards come out.

 

[dr.noob]

Yes, it's really a shame, but at this moment i don't have a budget to anything...Sorry guys.

I'll just leave it how it is now, stock cooling, and in the future do what's need to be done, thermalpads or an aftermarket cooler.

I need to find a job! :\