Overclock.net › Forums › Graphics Cards › AMD/ATI › HD 6850 memory bandwidth starved @ stock?
New Posts  All Forums:Forum Nav:

HD 6850 memory bandwidth starved @ stock?

post #1 of 12
Thread Starter 
Hi there.

Wanted to know if the 6850 at stock clocks are memory bandwidth starved? Reason I ask is in dirt 2, everything on high settings, the game plays well at 60fpp (vsync) but at a few points where there are many things happening at once (crown, water, lights and stuff, etc.) it goes down to +/-30fps. Now I checked with MSI afterburner in game monitoring to see what's going on, I saw that the GPU usage is 70% and the CPU usage is not maxxed either. So I came to the conclution that it's memory bandwidth starved, and I've read that OCing the mem gives good performance increase. I'm just a bit lazy to OC my card and test it for myself.

Would be nice if someone gives a linky that compares stock and OCed memory performance.

Thanks
*Mal Nai*
(18 items)
 
  
Reply
*Mal Nai*
(18 items)
 
  
Reply
post #2 of 12
Huge difference...

My 5770 has not let me down yet at the clocks I am at.

So your 6850 would beast if you OC
X79
(15 items)
 
First build ever
(10 items)
 
LGA 775
(9 items)
 
CPUMotherboardGraphicsRAM
Intel Core i7 3820 @4.3ghz stock volts Asus P9X79 Deluxe Sapphire Xtreme 5830 Crossfire @ 950/1200 16gb G Skill Sniper 2133mhz 
Hard DriveOptical DriveCoolingOS
OCZ Vertex 2 + 1TB WD Caviar Blue (Asus SSD Cac... Lite On DVD RW Noctua NH-D14 SE 2011 Windows 7 Pro 64 
MonitorKeyboardPowerCase
Hannspree HF237 Razer Black Widow Ultimate Rosewill Xtreme 950w Antec P280  
MouseMouse PadAudio
R.A.T. 7 Ripper XXL Klipsch Pro Media 2.1 (With onboard) 
CPUMotherboardGraphicsRAM
Athlon II X4 635 @ 3.5 on 1.34v GIGABYTE GA-890GPA-UD3H ATI Radeon HD 5770  12gb DDR3 (HyperX & Patriot) 
Hard DriveOptical DriveCoolingOS
500gb WD Caviar Blue Lite On 24x Noctua NH-D14 Windows 7 Pro 64 
PowerCase
Antec Neo Eco 400w NZXT Gamma 
CPUMotherboardGraphicsRAM
e5400 @ 3.6ghz EVGA nForce 750i SLI Galaxy GT240 512mb GDDR5 4gb of g skill DDR2 800 @ 867mhz 
Hard DriveCoolingOSPower
WD Blue 500gb Cooler Master Hyper N520 W7 Pro 64 bit Antec Neo Eco 400w 
Case
Lancool (Lian Li) K7 
  hide details  
Reply
X79
(15 items)
 
First build ever
(10 items)
 
LGA 775
(9 items)
 
CPUMotherboardGraphicsRAM
Intel Core i7 3820 @4.3ghz stock volts Asus P9X79 Deluxe Sapphire Xtreme 5830 Crossfire @ 950/1200 16gb G Skill Sniper 2133mhz 
Hard DriveOptical DriveCoolingOS
OCZ Vertex 2 + 1TB WD Caviar Blue (Asus SSD Cac... Lite On DVD RW Noctua NH-D14 SE 2011 Windows 7 Pro 64 
MonitorKeyboardPowerCase
Hannspree HF237 Razer Black Widow Ultimate Rosewill Xtreme 950w Antec P280  
MouseMouse PadAudio
R.A.T. 7 Ripper XXL Klipsch Pro Media 2.1 (With onboard) 
CPUMotherboardGraphicsRAM
Athlon II X4 635 @ 3.5 on 1.34v GIGABYTE GA-890GPA-UD3H ATI Radeon HD 5770  12gb DDR3 (HyperX & Patriot) 
Hard DriveOptical DriveCoolingOS
500gb WD Caviar Blue Lite On 24x Noctua NH-D14 Windows 7 Pro 64 
PowerCase
Antec Neo Eco 400w NZXT Gamma 
CPUMotherboardGraphicsRAM
e5400 @ 3.6ghz EVGA nForce 750i SLI Galaxy GT240 512mb GDDR5 4gb of g skill DDR2 800 @ 867mhz 
Hard DriveCoolingOSPower
WD Blue 500gb Cooler Master Hyper N520 W7 Pro 64 bit Antec Neo Eco 400w 
Case
Lancool (Lian Li) K7 
  hide details  
Reply
post #3 of 12
Quote:
Originally Posted by 1337guy;12586292 
Hi there.

Wanted to know if the 6850 at stock clocks are memory bandwidth starved? Reason I ask is in dirt 2, everything on high settings, the game plays well at 60fpp (vsync) but at a few points where there are many things happening at once (crown, water, lights and stuff, etc.) it goes down to +/-30fps. Now I checked with MSI afterburner in game monitoring to see what's going on, I saw that the GPU usage is 70% and the CPU usage is not maxxed either. So I came to the conclution that it's memory bandwidth starved, and I've read that OCing the mem gives good performance increase. I'm just a bit lazy to OC my card and test it for myself.

Would be nice if someone gives a linky that compares stock and OCed memory performance.

Thanks

Shouldn't be. If that was the case, it would matter in intensive load conditions (loading distant trees, characters, etc. with high res textures), not in intensive processing conditions.. I don't know, I'd guess the game coding itself affects it.
But you can try to raise the mem a bit and see if it improves those FPS much.
smile.gif
Just don't keep them raised for too long, cause heat does bad things to VRAM
My Rig
(14 items)
 
Ex-wife's Rig
(15 items)
 
 
CPUMotherboardGraphicsRAM
Core i5 4460 AsRock H81M-DG4 Sapphire Rx470 Platinum KVR 1600 16Gb 
Hard DriveHard DriveCoolingOS
2x Seagate 3Tb Samsung 850 EVO 120 Scythe Ninja 3 Rev.B Windows 10 Pro 
MonitorKeyboardPowerCase
Fujitsu Siemens A17-2A Logitech K280e SuperFlower SF-550K12XP Thermaltake Versa H25 
MouseAudio
Logitech G402 Sony MDR XD150 
CPUMotherboardGraphicsRAM
Athlon 750K 4.0Ghz AsRock FM2A75 Pro4+ Sapphire R9 270X Dual-X Kingston 2x4Gb 1600 
Hard DriveHard DriveOptical DriveCooling
Samsung 850 EVO 120  Western Digital 320Gb LiteON DVD-RW CoolerMaster Hyper Z600 
OSMonitorKeyboardPower
Windows 7 Pro x64 Toshiba 32" FullHD TV Logitech FSP Hexa 550 
CaseMouse
DeLUX Logitech 
  hide details  
Reply
My Rig
(14 items)
 
Ex-wife's Rig
(15 items)
 
 
CPUMotherboardGraphicsRAM
Core i5 4460 AsRock H81M-DG4 Sapphire Rx470 Platinum KVR 1600 16Gb 
Hard DriveHard DriveCoolingOS
2x Seagate 3Tb Samsung 850 EVO 120 Scythe Ninja 3 Rev.B Windows 10 Pro 
MonitorKeyboardPowerCase
Fujitsu Siemens A17-2A Logitech K280e SuperFlower SF-550K12XP Thermaltake Versa H25 
MouseAudio
Logitech G402 Sony MDR XD150 
CPUMotherboardGraphicsRAM
Athlon 750K 4.0Ghz AsRock FM2A75 Pro4+ Sapphire R9 270X Dual-X Kingston 2x4Gb 1600 
Hard DriveHard DriveOptical DriveCooling
Samsung 850 EVO 120  Western Digital 320Gb LiteON DVD-RW CoolerMaster Hyper Z600 
OSMonitorKeyboardPower
Windows 7 Pro x64 Toshiba 32" FullHD TV Logitech FSP Hexa 550 
CaseMouse
DeLUX Logitech 
  hide details  
Reply
post #4 of 12
Thread Starter 
Quote:
Originally Posted by Shev7chenko;12586329 
Huge difference...

My 5770 has not let me down yet at the clocks I am at.

So your 6850 would beast if you OC
I know it will be a beast if i oc it, but i honestly do not need to oc it atm, i get 60fps in most games i play and besides im not a "must be maXXed out looney". I can play at medium high, so will only OC when i really see the need. Just good to know i have headroom though. biggrin.gif

edit: I had a P4 celeron 2.6GHz with 1GB ram and a 6600GT before this, so i got kinda used to playing slide shows hahahaha.
Edited by 1337guy - 3/2/11 at 2:08pm
*Mal Nai*
(18 items)
 
  
Reply
*Mal Nai*
(18 items)
 
  
Reply
post #5 of 12
I have the same thing happen to me. I'm thinking it has something to do with the CPU and possible that damn Blue Ripple sound stuff.

i have noticed if you drop the Crowd setting to "Low" or whatever is just above off it helps a lot.
Primary
(16 items)
 
   
CPUMotherboardGraphicsRAM
Q9450 Gigabyte EP45-UD3P Powercolor PCS+ HD7870 Myst 4x 2GB G.skill DDR2 1100 
Hard DriveHard DriveHard DriveOptical Drive
OCZ Vertex 3 120GB WD Velociraptor 300GB Caviar Green 500GB LG 24x Super-Multi 
CoolingOSMonitorPower
Thermalright Venomous-X RT Win 7 Home Premium x64 ASUS VH222H Corsair HX650 
CaseMouseAudio
Corsair 600T SE White Cyborg R.A.T. 7 AKG K 702 
  hide details  
Reply
Primary
(16 items)
 
   
CPUMotherboardGraphicsRAM
Q9450 Gigabyte EP45-UD3P Powercolor PCS+ HD7870 Myst 4x 2GB G.skill DDR2 1100 
Hard DriveHard DriveHard DriveOptical Drive
OCZ Vertex 3 120GB WD Velociraptor 300GB Caviar Green 500GB LG 24x Super-Multi 
CoolingOSMonitorPower
Thermalright Venomous-X RT Win 7 Home Premium x64 ASUS VH222H Corsair HX650 
CaseMouseAudio
Corsair 600T SE White Cyborg R.A.T. 7 AKG K 702 
  hide details  
Reply
post #6 of 12
Quote:
Originally Posted by 1337guy;12586379 
I know it will be a beast if i oc it, but i honestly do not need to oc it atm, i get 60fps in most games i play and besides im not a "must be maXXed out looney". I can play at medium high, so will only OC when i really see the need. Just good to know i have headroom though. biggrin.gif

Nice. thumb.gif
X79
(15 items)
 
First build ever
(10 items)
 
LGA 775
(9 items)
 
CPUMotherboardGraphicsRAM
Intel Core i7 3820 @4.3ghz stock volts Asus P9X79 Deluxe Sapphire Xtreme 5830 Crossfire @ 950/1200 16gb G Skill Sniper 2133mhz 
Hard DriveOptical DriveCoolingOS
OCZ Vertex 2 + 1TB WD Caviar Blue (Asus SSD Cac... Lite On DVD RW Noctua NH-D14 SE 2011 Windows 7 Pro 64 
MonitorKeyboardPowerCase
Hannspree HF237 Razer Black Widow Ultimate Rosewill Xtreme 950w Antec P280  
MouseMouse PadAudio
R.A.T. 7 Ripper XXL Klipsch Pro Media 2.1 (With onboard) 
CPUMotherboardGraphicsRAM
Athlon II X4 635 @ 3.5 on 1.34v GIGABYTE GA-890GPA-UD3H ATI Radeon HD 5770  12gb DDR3 (HyperX & Patriot) 
Hard DriveOptical DriveCoolingOS
500gb WD Caviar Blue Lite On 24x Noctua NH-D14 Windows 7 Pro 64 
PowerCase
Antec Neo Eco 400w NZXT Gamma 
CPUMotherboardGraphicsRAM
e5400 @ 3.6ghz EVGA nForce 750i SLI Galaxy GT240 512mb GDDR5 4gb of g skill DDR2 800 @ 867mhz 
Hard DriveCoolingOSPower
WD Blue 500gb Cooler Master Hyper N520 W7 Pro 64 bit Antec Neo Eco 400w 
Case
Lancool (Lian Li) K7 
  hide details  
Reply
X79
(15 items)
 
First build ever
(10 items)
 
LGA 775
(9 items)
 
CPUMotherboardGraphicsRAM
Intel Core i7 3820 @4.3ghz stock volts Asus P9X79 Deluxe Sapphire Xtreme 5830 Crossfire @ 950/1200 16gb G Skill Sniper 2133mhz 
Hard DriveOptical DriveCoolingOS
OCZ Vertex 2 + 1TB WD Caviar Blue (Asus SSD Cac... Lite On DVD RW Noctua NH-D14 SE 2011 Windows 7 Pro 64 
MonitorKeyboardPowerCase
Hannspree HF237 Razer Black Widow Ultimate Rosewill Xtreme 950w Antec P280  
MouseMouse PadAudio
R.A.T. 7 Ripper XXL Klipsch Pro Media 2.1 (With onboard) 
CPUMotherboardGraphicsRAM
Athlon II X4 635 @ 3.5 on 1.34v GIGABYTE GA-890GPA-UD3H ATI Radeon HD 5770  12gb DDR3 (HyperX & Patriot) 
Hard DriveOptical DriveCoolingOS
500gb WD Caviar Blue Lite On 24x Noctua NH-D14 Windows 7 Pro 64 
PowerCase
Antec Neo Eco 400w NZXT Gamma 
CPUMotherboardGraphicsRAM
e5400 @ 3.6ghz EVGA nForce 750i SLI Galaxy GT240 512mb GDDR5 4gb of g skill DDR2 800 @ 867mhz 
Hard DriveCoolingOSPower
WD Blue 500gb Cooler Master Hyper N520 W7 Pro 64 bit Antec Neo Eco 400w 
Case
Lancool (Lian Li) K7 
  hide details  
Reply
post #7 of 12
Thread Starter 
Quote:
Originally Posted by clark_b;12586380 
I have the same thing happen to me. I'm thinking it has something to do with the CPU and possible that damn Blue Ripple sound stuff.

i have noticed if you drop the Crowd setting to "Low" or whatever is just above off it helps a lot.
Yeah forgot that that setting is set on low my side, i did notice the performance hit i got when it was higher yeah. thumb.gif
*Mal Nai*
(18 items)
 
  
Reply
*Mal Nai*
(18 items)
 
  
Reply
post #8 of 12
HD 6850's have a HUGE amount of headroom. AMD purposely kept the stock clocks low so that customers would have a reason to buy the HD 6870. Typically these cards will clock over 900/1100 stable with no voltage tweaking. Mine will do 950/1200 without increasing volts.

As you can see, overclock performance scales very well.

damric stock:
3dmark11pstock.png

damric unlocked and overclocked:
3dmark11poc.png
Light Gamer #1
(12 items)
 
Light Gamer #2
(10 items)
 
 
CPUMotherboardGraphicsGraphics
i3-6100 ASRock Fatal1ty Z170 Gaming K4/D3 MSI r7850 TFIII OC MSI r7850 TFIII OC 
RAMHard DriveCoolingOS
G,Skill TridentX OCZ Vector 150 TPC-612 Windows 10 
KeyboardPowerCaseMouse
G105 Rosewill Capstone 550M HAF XB M570 
CPUMotherboardGraphicsRAM
Athlon 860K MSI A88X-G45 MSI GTX 460 G.Skill RipjawsZ 
Hard DriveCoolingOSKeyboard
PNY Optima Hyper T4 Windows 10 Devastator 2 
PowerCase
Rosewill Valens DIYPC Ranger-R4-R 
  hide details  
Reply
Light Gamer #1
(12 items)
 
Light Gamer #2
(10 items)
 
 
CPUMotherboardGraphicsGraphics
i3-6100 ASRock Fatal1ty Z170 Gaming K4/D3 MSI r7850 TFIII OC MSI r7850 TFIII OC 
RAMHard DriveCoolingOS
G,Skill TridentX OCZ Vector 150 TPC-612 Windows 10 
KeyboardPowerCaseMouse
G105 Rosewill Capstone 550M HAF XB M570 
CPUMotherboardGraphicsRAM
Athlon 860K MSI A88X-G45 MSI GTX 460 G.Skill RipjawsZ 
Hard DriveCoolingOSKeyboard
PNY Optima Hyper T4 Windows 10 Devastator 2 
PowerCase
Rosewill Valens DIYPC Ranger-R4-R 
  hide details  
Reply
post #9 of 12
is that on 3dmark 11?
Primary
(16 items)
 
   
CPUMotherboardGraphicsRAM
Q9450 Gigabyte EP45-UD3P Powercolor PCS+ HD7870 Myst 4x 2GB G.skill DDR2 1100 
Hard DriveHard DriveHard DriveOptical Drive
OCZ Vertex 3 120GB WD Velociraptor 300GB Caviar Green 500GB LG 24x Super-Multi 
CoolingOSMonitorPower
Thermalright Venomous-X RT Win 7 Home Premium x64 ASUS VH222H Corsair HX650 
CaseMouseAudio
Corsair 600T SE White Cyborg R.A.T. 7 AKG K 702 
  hide details  
Reply
Primary
(16 items)
 
   
CPUMotherboardGraphicsRAM
Q9450 Gigabyte EP45-UD3P Powercolor PCS+ HD7870 Myst 4x 2GB G.skill DDR2 1100 
Hard DriveHard DriveHard DriveOptical Drive
OCZ Vertex 3 120GB WD Velociraptor 300GB Caviar Green 500GB LG 24x Super-Multi 
CoolingOSMonitorPower
Thermalright Venomous-X RT Win 7 Home Premium x64 ASUS VH222H Corsair HX650 
CaseMouseAudio
Corsair 600T SE White Cyborg R.A.T. 7 AKG K 702 
  hide details  
Reply
post #10 of 12
I think I know the answer to your problem. You have VSYNC on, which means the computer will have to get the frames done at the right time to sync them. To do this it needs a factor of 60fps. 60 will VSYNC, so will 30 (each frame repeated twice), 20 (three times), 10 (six), etc. So most of the time your GPU is fine with 60. Well done, 6850 is honestly the best budget card of all time. Can even take a chunk out of Crysis with no Anti-Aliasing. Way better in value than my 6970. But when there is a lot of rendering to be done in a series of frames and the framerate drops to 55, say, the problem shows. 60 is not divisible by 55, so the system will force it back to 30, the largest number your monitor's 60fps refresh rate is divisible by. Then 20 if 30 is still too much, and so on.

The framerate may drop a few frames below 60fps without a reduction but I don't know by how much. But it happens to me in Far Cry 2 all the time. Max settings, 8x MSAA and 1920x1080 resolution it will reduce in areas of high scenery and long distance drawing.

I have not been told this but it is the best possible explanation, which I figured out by a little bit of reasoning in the back of my head.

The solution: Lose a few anti-aliases. I think the 6850 would only drop below 60fps at 1920x1080 with quite a few anti-aliases. And if you have Adaptive MultiSampling, SuperSampling or Edge-Detect Anti-Aliasing enabled, ditch them, including Morphological Filtering. Edge-Detect and Morphological Filtering look bad in most titles (to my oppinion) and Adaptive MultiSampling and SuperSampling are a waste of GPU time unless you have several GPU's and only one monitor. Edge-Detect put all the way up in unplayable in most modern titles with single-GPU configurations. Even the amazing GTX 580.

What resolution are you at? That would give me a better idea of what your graphics solution is capable of. I only have the DiRT2 Demo but it is amazing and I want it so bad. It came with AMD GPU's a while ago (Sapphire Technology?) but my HD 6970 didn't come with BFBC2 Vietnam like it said on the box. Only a discount to buy the real BFBC2 and get the Vietnam edition free with that. Load of bull. Anybody else have had this problem?

Have fun with that. I have to use 2 PSU's to run this GPU. 500W isn't enough and I only have an i3-530 which I put back to stock from 4GHz to save power. smil3dbd4e4c2e742.gif Tell me if that seems like a good explanation, and if dropping just one level of Anti-Aliasing helps make the problem less frequent. What level do you have on now, though? smile.gif
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: AMD/ATI
Overclock.net › Forums › Graphics Cards › AMD/ATI › HD 6850 memory bandwidth starved @ stock?