How to overclock a 7850 past 1050MHz?

MoodyB · 2 May 2012 at 21:07

SickBeast said:
What's interesting is that there is a 5% performance improvement from 4400-->5000, but then a 1% improvement from 5000-->5600.

Mookzen explained this a few pages back :

"Some time ago ATI introduced memory error correction routines on their cards, meaning that instead of going all BSOD, producing artifacts or crashing the display driver, the card will quietly repeat failed actions multiple times until it works.

What this means in practice is that at some point in your overclocking you will actually start to lose performance even though the card seems stable at the higher clock, this is why running benchmarks is much more important nowadays to see whether the performance gains are legitimate.

You need to find the sweetspot, the highest balance between memory and core overclocks before them routines kick in (core clock being the more valuable of the 2), start by keeping the core and reducing memory."

SickBeast · 2 May 2012 at 22:36

MoodyB said:
Mookzen explained this a few pages back :

"Some time ago ATI introduced memory error correction routines on their cards, meaning that instead of going all BSOD, producing artifacts or crashing the display driver, the card will quietly repeat failed actions multiple times until it works.

What this means in practice is that at some point in your overclocking you will actually start to lose performance even though the card seems stable at the higher clock, this is why running benchmarks is much more important nowadays to see whether the performance gains are legitimate.

You need to find the sweetspot, the highest balance between memory and core overclocks before them routines kick in (core clock being the more valuable of the 2), start by keeping the core and reducing memory."

Well, with Crysis benchmarking, it increased linearly with increase in memory speed:

-----------------------------------------------------------------------------

Crysis:

5000mhz - 47.7fps
5200mhz - 48.2fps
5400mhz - 48.7fps
5600mhz - 49fps

-----------------------------------------------------------------------------

MoodyB · 2 May 2012 at 22:54

Just means you haven't found your limit then. Heaven can vary its results from each run, as can most benchmarks.

If Crysis & other benchmarks say otherwise, then I'd believe the majority

pieman109 · 2 May 2012 at 23:01

On a side note, I re-installed the original crysis, the one on the island with Nomad, and I can safely say that has to be one of the prettiest games I've ever seen, especially considering it was released in 2007, and on top of that, with this card VTX 7850 running overclocked at 1175/5800 @ 1.185v, and an i5 760 @ 4.0ghz, it runs really well with all settings maxed out except motion blur (can't stand that, makes me queasy) at 1080p and I suppose I average 45-50fps (and those fps are fairly constant, no dips that I've noticed) never thought I'd see the day when it'd run this well

SickBeast · 2 May 2012 at 23:46

pieman109 said:
On a side note, I re-installed the original crysis, the one on the island with Nomad, and I can safely say that has to be one of the prettiest games I've ever seen, especially considering it was released in 2007, and on top of that, with this card VTX 7850 running overclocked at 1175/5800 @ 1.185v, and an i5 760 @ 4.0ghz, it runs really well with all settings maxed out except motion blur (can't stand that, makes me queasy) at 1080p and I suppose I average 45-50fps (and those fps are fairly constant, no dips that I've noticed) never thought I'd see the day when it'd run this well

You should try Crysis Warhead. It runs somewhat faster with slightly better visuals IMO.

pieman109 · 2 May 2012 at 23:47

SickBeast said:
You should try Crysis Warhead. It runs somewhat faster with slightly better visuals IMO.

I've tried all three

and I reckon that the original game has the nicest graphics personally, warhead looks a bit "cartoony" to me.

Vinno · 3 May 2012 at 00:22

I am so tempted to get one of these bad boys.

If it was guaranteed to get the max overclocks that some of you guys are getting I'd have got one last week. Not sure I want to play this "lottery" though lol.

pieman109 · 3 May 2012 at 00:46

Vinno said:
I am so tempted to get one of these bad boys.

If it was guaranteed to get the max overclocks that some of you guys are getting I'd have got one last week. Not sure I want to play this "lottery" though lol.

I would suggest that 1150 core at even a reasonable voltage, say 1.175v is easily doable for nearly all the cards seen in this thread and the difference in "real world" performance isn't that big between 1150 and 1200, probably a coupla fps and thats it. Even at 1150, you're getting an increase of nigh on 300mhz in overclock and thats not to be sniffed at.

MoodyB · 3 May 2012 at 01:02

pieman109 said:
Even at 1150, you're getting an increase of nigh on 300mhz in overclock and thats not to be sniffed at.

At 1150 you'll be around stock GTX 580 speeds. With the bonus of 500mb more vram.

In the Crysis2 bench Hex's card at 1225/5800 managed 51.8 with a [email protected]. My 580 at stock clocks did 50.0 with an i5@4ghz.

Vinno · 3 May 2012 at 01:13

Hmm. I'm really very tempted. I originally planned to get a 7970 because I like to buy a card for the next 3-4 years. I'm currently running a 5850 which I've had for 3ish years I think and even though it can run every game on at least high settings, I really like to have stuff on the very highest. I cant really tell any difference.. its just a pet peeve of mine I suppose.

But the thought of saving £180ish is really very tempting.

The only 7850s in stock at OCUK atm are:

http://www.overclockers.co.uk/showproduct.php?prodid=GX-005-VX&groupid=701&catid=56&subcat=411

and

http://www.overclockers.co.uk/showproduct.php?prodid=GX-295-SP&groupid=701&catid=56&subcat=411

Any reccomendations on these two? Or should I wait for the Frozr IV?

Vanilla · 3 May 2012 at 01:24

Vinno said:
Hmm. I'm really very tempted. I originally planned to get a 7970 because I like to buy a card for the next 3-4 years. I'm currently running a 5850 which I've had for 3ish years I think and even though it can run every game on at least high settings, I really like to have stuff on the very highest. I cant really tell any difference.. its just a pet peeve of mine I suppose.

But the thought of saving £180ish is really very tempting.

The only 7850s in stock at OCUK atm are:

http://www.overclockers.co.uk/showproduct.php?prodid=GX-005-VX&groupid=701&catid=56&subcat=411

and

http://www.overclockers.co.uk/showproduct.php?prodid=GX-295-SP&groupid=701&catid=56&subcat=411

Any reccomendations on these two? Or should I wait for the Frozr IV?

I went for the VTX yesterday, I hear it can be a little loud but I plan on changing up the fan settings.

Also note this:

http://forums.overclockers.co.uk/showthread.php?t=18395778

RounD · 3 May 2012 at 07:05

Is anyone else getting a weird pink screen when they get into windows or load a game? My card appears to be working fine and it's stable and it's not really a problem but I never had anything like this with my Nvidia cards. It's like the driver is crashing and then working again? On latest drivers btw.

kilnborn · 3 May 2012 at 08:39

Some data for y'all

Picked up a Sapphire (non-OC) 7850 last week. Some data for y'all to keep tabs on the various cards:

Stock voltage: 1.138v (typical). Stock temps: 60c

Max OC on stock voltage: 1100/5200. Temps: 63c (this is above average).

Max OC on 1.205v: 1190/5400. Temps: 66c

Here're my 3d mark scores on various memory settings, using 860 mhz core:

4800MHz : 4883
5000MHz : 4926
5200MHz : 4922
5300MHz : 4944
5400MHz : 4964
5500MHz : 4974
5600MHz : 4929
5700MHz : 4961
5800MHz : 4968

I'm loath to try 1.225v, simply because my stock voltage OC is so good. My temps are good, I could probably go higher, but why?

Antec 300 case, Phenom II x4 @ 3.9ghz, stock fans.

All in all, i got a "good", but not "great" chip. Good enough for me.

HeX · 3 May 2012 at 08:48

Vinno said:
But the thought of saving £180ish is really very tempting.

The only 7850s in stock at OCUK atm are:

http://www.overclockers.co.uk/showproduct.php?prodid=GX-005-VX&groupid=701&catid=56&subcat=411

and

http://www.overclockers.co.uk/showproduct.php?prodid=GX-295-SP&groupid=701&catid=56&subcat=411

Any reccomendations on these two? Or should I wait for the Frozr IV?

Neither, get the HIS card for £185. But get your order in quick as the price will go up when stock comes in (should be today).

RounD said:
Is anyone else getting a weird pink screen when they get into windows or load a game? My card appears to be working fine and it's stable and it's not really a problem but I never had anything like this with my Nvidia cards. It's like the driver is crashing and then working again? On latest drivers btw.

Can't say i've had anything like that.

Dave777 · 3 May 2012 at 09:43

Right now if I were buying I'd go for the HIS card on special for £185, improved cooler, and a great price and you've just as much chance as hitting a high OC as any of the other brands.

Cheers for that. Seems just what I want.

MyUsualOnesUsed · 3 May 2012 at 12:31

RounD said:
Is anyone else getting a weird pink screen when they get into windows or load a game? My card appears to be working fine and it's stable and it's not really a problem but I never had anything like this with my Nvidia cards. It's like the driver is crashing and then working again? On latest drivers btw.

Is it overclocked?

Twirlywoos · 3 May 2012 at 15:15

HeX said:
Luck of the draw really, there have been great and duff cards from all brands.

What helps is having a better cooler so you can put more volts through without the heat getting too much.

The VTX/Club3D's have problems there as their stock coolers aren't up to the task of lots of extra volts.

The Sapphire and MSI's handle it better as they have big uprated coolers, so people can put more volts through to get higher OC's without the cards getting too hot.

Right now if I were buying I'd go for the HIS card on special for £185, improved cooler, and a great price and you've just as much chance as hitting a high OC as any of the other brands.

I've gone for that card.

Hopefully it will be dispatched sooner than later.

RevBillyG · 3 May 2012 at 15:21

*Mini-rant*
I hate it when web-shops show the item as in stock until after they take your money then show it as available in 4-10 days

The only reason I ordered the MSI is that it was shown as in stock. Bah!

Prozel · 3 May 2012 at 20:14

RevBillyG said:
*Mini-rant*
I hate it when web-shops show the item as in stock until after they take your money then show it as available in 4-10 days The only reason I ordered the MSI is that it was shown as in stock. Bah!

Tell me about it! I was going to get a MSI myself but ofcourse the store made a mistake so there was off course none available!

OT: I gave the voltage a nudge so it's close to 1200 which so far hasn't resulted in any problem with 1100mzh. Great succes!

RounD · 3 May 2012 at 21:04

MyUsualOnesUsed said:
Is it overclocked?

Yeah but it does it at the stock OC clocks aswell. It's not really a problem because the card has been running great with everything I've thrown at it, it's just really weird.