crazyates
							
								Legendary 
								 
								  Offline
								Activity: 952 
								Merit: 1000
								 
								
								
								
								
								 
							 
						 | 
								
							
								  | 
								
												
												 June 18, 2012, 03:38:13 PM  | 
										  
								 | 
							  
									  
							What's the best brand for 5970 in terms of overclocking/Mhps?
  I got my Gigabyte 5870 to 450Mbps without much sweat, which is quite high for a 5870.
  But my Gigabyte 5970s can't seem to go post 700Mhps without freezing the whole system  :/
  I'm running them at 180/800MHz/Default voltage
  Mbps? You mean MH/s?    I kid... It's really card dependent. I like PowerColor, Sapphire, and Asus. A lot of people have good luck with Gigabyte. I've heard to stay away from XFX and Diamond, but again, YMMV. There is no BEST brand for OCing.  Also, while a 5970 is technically 2x 5870s in one card, the voltages are lower to keep the power/temps down. Stock voltage on a 5870 is 1.174, while stock voltage on a 5970 is 1.050. If you lowered your 5870 down to 1.05, you won't be getting 450MH/s.  If you raised your 5970 to 1.174, you MIGHT be able to get 400+ per core, but it would be a very bad idea. Power draw increases, temps become too much for the shared cooler, and your VRM temps would be through the roof. Not a good idea. Side note: Here are my 5870 speeds, for undervolting comparison: 460MH/s - 980/300/1.174 - My "all out" setting 425MH/s - 925/300/1.000 - My "max profit" setting 350MH/s - 755/300/0.950 - My "keep the temps down" setting. I think my card can get higher clocks at each voltages than average, so yours may be a little lower.   
						 | 
					 
					
						
							
							 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								| 
							luffy
							
						 | 
								
							
								  | 
								
												
												 June 18, 2012, 04:01:10 PM  | 
										  
								 | 
							  
									  
							all of my 5970 (8+) after a continuing year of operation at stock 725/300 and nearly 90c are off! some of them with fun problems (easily fixed) others with BSOD (never fixed!) all my one core cards 5850/5870 (10+) have no problem at all up to now! i wonder if dual cards are not designed for continues full operation at high temp conditions! 
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							crazyates
							
								Legendary 
								 
								  Offline
								Activity: 952 
								Merit: 1000
								 
								
								
								
								
								 
							 
						 | 
								
							
								  | 
								
												
												 June 18, 2012, 04:06:42 PM  | 
										  
								 | 
							  
									  
							all of my 5970 (8+) after a continuing year of operation at stock 725/300 and nearly 90c are off! some of them with fun problems (easily fixed) others with BSOD (never fixed!) all my one core cards 5850/5870 (10+) have no problem at all up to now! i wonder if dual cards are not designed for continues full operation at high temp conditions!
  I doubt your single core GPUs were run at 90c, were they? I'm betting if you had undervolted them a bit, and had better airflow, they'd still be running.   
						 | 
					 
					
						
							
							 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								| 
							Aseras
							
						 | 
								
							
								  | 
								
												
												 June 18, 2012, 10:07:05 PM  | 
										  
								 | 
							  
									  
							What's the best brand for 5970 in terms of overclocking/Mhps?
  I got my Gigabyte 5870 to 450Mbps without much sweat, which is quite high for a 5870.
  But my Gigabyte 5970s can't seem to go post 700Mhps without freezing the whole system  :/
  I'm running them at 180/800MHz/Default voltage
  All of mine are XFX Black edition. all will do 900mhz both cores on 1.05v and get ~800mhash. I can run the second "cooler" cores up to 950 on 1.05 but it's simpler this way.  
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							Vorksholk
							
								Legendary 
								 
								  Offline
								Activity: 1713 
								Merit: 1029
								 
								
								
								
								
								 
								 
							 
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 12:22:17 AM  | 
										  
								 | 
							  
									  
							Tried an over clock to 913MHz core clock and 1100mV, VRM's at 100C and GPU's at 75 with fan@~90% (loud...). 
  Been stable for half an hour so far, and still running, we'll see... 
						 | 
					 
					
						
							
							 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							jjiimm_64
							
								Legendary 
								 
								  Offline
								Activity: 1876 
								Merit: 1000
								
								
								
								
								  
							 
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 01:45:45 AM  | 
										  
								 | 
							  
									  
							 you guys must have really cheap electricity! 
						 | 
					 
					
						
							
							 
							1jimbitm6hAKTjKX4qurCNQubbnk2YsFw 
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								| 
							bulanula
							
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 12:49:29 PM  | 
										  
								 | 
							  
									  
							Tried an over clock to 913MHz core clock and 1100mV, VRM's at 100C and GPU's at 75 with fan@~90% (loud...). 
  Been stable for half an hour so far, and still running, we'll see...
  All of this overclocking on 5970 is a great way to kill your card.  BUT keep going, less difficulty for moi !  Don't mind AMD and them stupidly making undervolt because you know better, right ?  Look at above poster showing how his cards died, hope yours do the same !  
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							jjiimm_64
							
								Legendary 
								 
								  Offline
								Activity: 1876 
								Merit: 1000
								
								
								
								
								  
							 
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 02:58:42 PM  | 
										  
								 | 
							  
									  
							I'm with you, let them burn them up...  not only is the electricity the issue.  this rig as been running without stopping since My9th.  I think I upgraded cgminer that day..   I cant remember exactly how many watts at the wall, i have that in another post..  i think 850-900 cgminer version 2.3.6 - Started: [May 9, 2012, 8:03 pm]    Rig:miner2 (5s):2457.99  (avg): 2420.22 Mh/s  |    H: 122.69  Q:1882472   A:1915344   R:13328   HW:0   E:?%   U:32.75/m TQ:?   ST:2356   SS:?   DW:166711   NB:5865   LW:4155588   GF:1176   RF:1321 Connected to http://gpumax.com:8332 with LP as user ? Value: GPU 0:	70.0C	3108RPM 	49% 	119	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:238551	R:1690	HW:0	U:4.08/m 	I: 7 GPU 1:	72.5C	3108RPM 	49% 	122	| 306.9/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239227	R:1712	HW:0	U:4.09/m 	I: 7 GPU 2:	72.0C	3513RPM 	57% 	129	| 307.3/302.0Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239375	R:1636	HW:0	U:4.09/m 	I: 7 GPU 3:	68.5C	3513RPM 	57% 	126	| 307.4/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239106	R:1747	HW:0	U:4.09/m 	I: 7 GPU 4:	70.0C	3290RPM 	50% 	120	| 307.6/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239754	R:1673	HW:0	U:4.10/m 	I: 7 GPU 5:	70.5C	3290RPM 	50% 	121	| 307.2/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239850	R:1633	HW:0	U:4.10/m 	I: 7 GPU 6:	72.5C	3257RPM 	51% 	124	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239795	R:1658	HW:0	U:4.10/m 	I: 7 GPU 7:	71.5C	3257RPM 	51% 	123	| 307.6/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239686	R:1579	HW:0	U:4.10/m 	I: 7
   
						 | 
					 
					
						
							
							 
							1jimbitm6hAKTjKX4qurCNQubbnk2YsFw 
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							crazyates
							
								Legendary 
								 
								  Offline
								Activity: 952 
								Merit: 1000
								 
								
								
								
								
								 
							 
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 03:44:21 PM  | 
										  
								 | 
							  
									  
							I'm with you, let them burn them up...  not only is the electricity the issue.  this rig as been running without stopping since My9th.  I think I upgraded cgminer that day..   I cant remember exactly how many watts at the wall, i have that in another post..  i think 850-900 cgminer version 2.3.6 - Started: [May 9, 2012, 8:03 pm]    Rig:miner2 (5s):2457.99  (avg): 2420.22 Mh/s  |    H: 122.69  Q:1882472   A:1915344   R:13328   HW:0   E:?%   U:32.75/m TQ:?   ST:2356   SS:?   DW:166711   NB:5865   LW:4155588   GF:1176   RF:1321 Connected to http://gpumax.com:8332 with LP as user ? Value: GPU 0:	70.0C	3108RPM 	49% 	119	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:238551	R:1690	HW:0	U:4.08/m 	I: 7 GPU 1:	72.5C	3108RPM 	49% 	122	| 306.9/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239227	R:1712	HW:0	U:4.09/m 	I: 7 GPU 2:	72.0C	3513RPM 	57% 	129	| 307.3/302.0Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239375	R:1636	HW:0	U:4.09/m 	I: 7 GPU 3:	68.5C	3513RPM 	57% 	126	| 307.4/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239106	R:1747	HW:0	U:4.09/m 	I: 7 GPU 4:	70.0C	3290RPM 	50% 	120	| 307.6/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239754	R:1673	HW:0	U:4.10/m 	I: 7 GPU 5:	70.5C	3290RPM 	50% 	121	| 307.2/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239850	R:1633	HW:0	U:4.10/m 	I: 7 GPU 6:	72.5C	3257RPM 	51% 	124	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239795	R:1658	HW:0	U:4.10/m 	I: 7 GPU 7:	71.5C	3257RPM 	51% 	123	| 307.6/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239686	R:1579	HW:0	U:4.10/m 	I: 7
  Very nice. Is there a reason you run -I 7 instead of -I 8?   
						 | 
					 
					
						
							
							 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								| 
							Aseras
							
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 04:09:54 PM  | 
										  
								 | 
							  
									  
							 I'm with you, let them burn them up...  not only is the electricity the issue.  this rig as been running without stopping since My9th.  I think I upgraded cgminer that day..  
  I cant remember exactly how many watts at the wall, i have that in another post..  i think 850-900
 
 
 Power or cooling isn't an issue for me. My 5970's are rock solid at 900mhz core. They only downtime they get is when I switch pools up upgrade cgminer. They've been running full on since I got them, a LONG time ago. Minimal maintenance, clean dust and touch up the TIM if temps creep etc.  
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							jjiimm_64
							
								Legendary 
								 
								  Offline
								Activity: 1876 
								Merit: 1000
								
								
								
								
								  
							 
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 04:15:05 PM  | 
										  
								 | 
							  
									  
							
  Very nice. Is there a reason you run -I 7 instead of -I 8? 
 
 well, i tried 8 and 9,  they seam to jump around too much..  tell you what, I will put this rig at I8 for today, lets see how it does. putting them at I8 now.  (thank you webmon)  
						 | 
					 
					
						
							
							 
							1jimbitm6hAKTjKX4qurCNQubbnk2YsFw 
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							jjiimm_64
							
								Legendary 
								 
								  Offline
								Activity: 1876 
								Merit: 1000
								
								
								
								
								  
							 
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 04:16:53 PM  | 
										  
								 | 
							  
									  
							 I'm with you, let them burn them up...  not only is the electricity the issue.  this rig as been running without stopping since My9th.  I think I upgraded cgminer that day..  
  I cant remember exactly how many watts at the wall, i have that in another post..  i think 850-900
 
 
 Power or cooling isn't an issue for me. My 5970's are rock solid at 900mhz core. They only downtime they get is when I switch pools up upgrade cgminer. They've been running full on since I got them, a LONG time ago. Minimal maintenance, clean dust and touch up the TIM if temps creep etc. May I ask who is paying for your power then?  
						 | 
					 
					
						
							
							 
							1jimbitm6hAKTjKX4qurCNQubbnk2YsFw 
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							jjiimm_64
							
								Legendary 
								 
								  Offline
								Activity: 1876 
								Merit: 1000
								
								
								
								
								  
							 
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 04:18:05 PM  | 
										  
								 | 
							  
									  
							OK,  i have had them at 8 for about 10 minutes..  they finally stabilized.... as you can see, the heatindex has climbed 5 points.  from 122 to 127, with no increase in MH will post this again after my round of golf   cgminer version 2.3.6 - Started: [May 9, 2012, 8:03 pm]    Rig:miner2 (5s):2455.98  (avg): 2420.28 Mh/s  |    H: 127.5  Q:1885119   A:1918524   R:13365   HW:0   E:?%   U:32.75/m TQ:?   ST:2357   SS:?   DW:166980   NB:5871   LW:4166227   GF:1176   RF:1321 Connected to http://gpumax.com:8332 with LP as user ? Value: GPU 0:	68.5C	3464RPM 	56% 	125	| 307.0/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:238920	R:1693	HW:0	U:4.08/m 	I: 8 GPU 1:	70.0C	3464RPM 	56% 	126	| 306.7/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239633	R:1719	HW:0	U:4.09/m 	I: 8 GPU 2:	72.0C	3702RPM 	61% 	133	| 307.2/302.0Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239798	R:1642	HW:0	U:4.09/m 	I: 8 GPU 3:	68.5C	3706RPM 	61% 	130	| 307.0/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239522	R:1751	HW:0	U:4.09/m 	I: 8 GPU 4:	69.5C	3449RPM 	53% 	123	| 307.0/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:240170	R:1679	HW:0	U:4.10/m 	I: 8 GPU 5:	70.5C	3449RPM 	53% 	124	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:240237	R:1640	HW:0	U:4.10/m 	I: 8 GPU 6:	70.5C	3529RPM 	60% 	131	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:240166	R:1660	HW:0	U:4.10/m 	I: 8 GPU 7:	70.5C	3529RPM 	60% 	131	| 307.0/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:240078	R:1581	HW:0	U:4.10/m 	I: 8
   
						 | 
					 
					
						
							
							 
							1jimbitm6hAKTjKX4qurCNQubbnk2YsFw 
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								| 
							Aseras
							
						 | 
								
							
								  | 
								
												
												 June 19, 2012, 11:16:05 PM Last edit: June 19, 2012, 11:39:05 PM by Aseras  | 
										  
								 | 
							  
									  
							 I'm with you, let them burn them up...  not only is the electricity the issue.  this rig as been running without stopping since My9th.  I think I upgraded cgminer that day..  
  I cant remember exactly how many watts at the wall, i have that in another post..  i think 850-900
 
 
 Power or cooling isn't an issue for me. My 5970's are rock solid at 900mhz core. They only downtime they get is when I switch pools up upgrade cgminer. They've been running full on since I got them, a LONG time ago. Minimal maintenance, clean dust and touch up the TIM if temps creep etc. May I ask who is paying for your power then? Power is included in my collocation/lease at my data center   . Most of my rigs are 1gpu web servers. They all run low intensity so it doesn't affect normal operation. Most of them are for development or sandboxing anyways. I have 6 full racks.  
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							jjiimm_64
							
								Legendary 
								 
								  Offline
								Activity: 1876 
								Merit: 1000
								
								
								
								
								  
							 
						 | 
								
							
								  | 
								
												
												 June 20, 2012, 12:47:44 AM  | 
										  
								 | 
							  
									  
							I'm with you, let them burn them up...  not only is the electricity the issue.  this rig as been running without stopping since My9th.  I think I upgraded cgminer that day..   I cant remember exactly how many watts at the wall, i have that in another post..  i think 850-900 cgminer version 2.3.6 - Started: [May 9, 2012, 8:03 pm]    Rig:miner2 (5s):2457.99  (avg): 2420.22 Mh/s  |    H: 122.69  Q:1882472   A:1915344   R:13328   HW:0   E:?%   U:32.75/m TQ:?   ST:2356   SS:?   DW:166711   NB:5865   LW:4155588   GF:1176   RF:1321 Connected to http://gpumax.com:8332 with LP as user ? Value: GPU 0:	70.0C	3108RPM 	49% 	119	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:238551	R:1690	HW:0	U:4.08/m 	I: 7 GPU 1:	72.5C	3108RPM 	49% 	122	| 306.9/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239227	R:1712	HW:0	U:4.09/m 	I: 7 GPU 2:	72.0C	3513RPM 	57% 	129	| 307.3/302.0Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239375	R:1636	HW:0	U:4.09/m 	I: 7 GPU 3:	68.5C	3513RPM 	57% 	126	| 307.4/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239106	R:1747	HW:0	U:4.09/m 	I: 7 GPU 4:	70.0C	3290RPM 	50% 	120	| 307.6/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239754	R:1673	HW:0	U:4.10/m 	I: 7 GPU 5:	70.5C	3290RPM 	50% 	121	| 307.2/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239850	R:1633	HW:0	U:4.10/m 	I: 7 GPU 6:	72.5C	3257RPM 	51% 	124	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239795	R:1658	HW:0	U:4.10/m 	I: 7 GPU 7:	71.5C	3257RPM 	51% 	123	| 307.6/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:239686	R:1579	HW:0	U:4.10/m 	I: 7
  Very nice. Is there a reason you run -I 7 instead of -I 8?  so, they ahve been running all day at I8  ..  not much difference.  ..  cant judge heat cause it was hot today.  going back to 7 cgminer version 2.3.6 - Started: [May 9, 2012, 8:03 pm]    Rig:miner2 (5s):2455.03  (avg): 2420.51 Mh/s  |    H: 130.94  Q:1899083   A:1935528   R:13638   HW:0   E:?%   U:32.76/m TQ:?   ST:2372   SS:?   DW:168305   NB:5905   LW:4227166   GF:1179   RF:1328 Connected to http://gpumax.com:8332 with LP as user ? Value: GPU 0:	68.0C	3597RPM 	59% 	127	| 306.9/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:241059	R:1721	HW:0	U:4.08/m 	I: 8 GPU 1:	70.0C	3597RPM 	59% 	129	| 307.4/302.7Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:241768	R:1744	HW:0	U:4.09/m 	I: 8 GPU 2:	71.0C	4100RPM 	72% 	143	| 307.2/302.1Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:241916	R:1671	HW:0	U:4.09/m 	I: 8 GPU 3:	67.5C	4100RPM 	72% 	140	| 307.1/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:241606	R:1792	HW:0	U:4.09/m 	I: 8 GPU 4:	70.5C	3591RPM 	56% 	127	| 306.7/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:242321	R:1717	HW:0	U:4.10/m 	I: 8 GPU 5:	70.5C	3591RPM 	56% 	127	| 307.0/302.7Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:242354	R:1676	HW:0	U:4.10/m 	I: 8 GPU 6:	70.5C	3591RPM 	58% 	129	| 306.5/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:242295	R:1698	HW:0	U:4.10/m 	I: 8 GPU 7:	70.5C	3591RPM 	57% 	128	| 306.3/302.6Mh/s | 	99% |	675Mhz 	300Mhz 	0.95V 	A:242209	R:1619	HW:0	U:4.10/m 	I: 8
   
						 | 
					 
					
						
							
							 
							1jimbitm6hAKTjKX4qurCNQubbnk2YsFw 
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								| 
							Aseras
							
						 | 
								
							
								  | 
								
												
												 June 20, 2012, 02:41:42 AM  | 
										  
								 | 
							  
									  
							Anything above 5 won't change hash rate on a dedicated box. 7 and below will allow the box to be usable as a pc and not stutter or crash or just be slow. It will slightly slow performance if you are doing other things. 
  My main work box is two 6990 at 880 and i7. It's perfectly usable and quiet all while getting 1.5ghash.  
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							zvs
							
								Legendary 
								 
								  Offline
								Activity: 1694 
								Merit: 1003
								 
								
								
								
								
								 
								 
							 
						 | 
								
							
								  | 
								
												
												 June 21, 2012, 02:40:00 PM  | 
										  
								 | 
							  
									  
							What's the best brand for 5970 in terms of overclocking/Mhps?
  I got my Gigabyte 5870 to 450Mbps without much sweat, which is quite high for a 5870.
  But my Gigabyte 5970s can't seem to go post 700Mhps without freezing the whole system  :/
  I'm running them at 180/800MHz/Default voltage
  Mbps? You mean MH/s?    I kid... It's really card dependent. I like PowerColor, Sapphire, and Asus. A lot of people have good luck with Gigabyte. I've heard to stay away from XFX and Diamond, but again, YMMV. There is no BEST brand for OCing.  Also, while a 5970 is technically 2x 5870s in one card, the voltages are lower to keep the power/temps down. Stock voltage on a 5870 is 1.174, while stock voltage on a 5970 is 1.050. If you lowered your 5870 down to 1.05, you won't be getting 450MH/s.  If you raised your 5970 to 1.174, you MIGHT be able to get 400+ per core, but it would be a very bad idea. Power draw increases, temps become too much for the shared cooler, and your VRM temps would be through the roof. Not a good idea. Side note: Here are my 5870 speeds, for undervolting comparison: 460MH/s - 980/300/1.174 - My "all out" setting 425MH/s - 925/300/1.000 - My "max profit" setting 350MH/s - 755/300/0.950 - My "keep the temps down" setting. I think my card can get higher clocks at each voltages than average, so yours may be a little lower.  you should try higher at 0.950v...   mine has been stable for 200+ hrs at 830/195/0.950 the next step for me is 940/195/1.112 then 1010/195/1.175 it's xfx non-ref (hmm or maybe a sapphire non-ref...  haha)  
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								| 
							Sant001
							
						 | 
								
							
								  | 
								
												
												 June 25, 2012, 10:07:09 AM  | 
										  
								 | 
							  
									  
							How much power one needs to power 3x to 5x 5970s?
  I have 2x 5970 at 1200W, the moment I try use 3x the thing gets really unstable and I can just assume it's due to insufficient power.
  Running them with under clocked memory/default core/default voltage. 
						 | 
					 
					
						| 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							crazyates
							
								Legendary 
								 
								  Offline
								Activity: 952 
								Merit: 1000
								 
								
								
								
								
								 
							 
						 | 
								
							
								  | 
								
												
												 June 25, 2012, 02:36:03 PM  | 
										  
								 | 
							  
									  
							How much power one needs to power 3x to 5x 5970s?
  I have 2x 5970 at 1200W, the moment I try use 3x the thing gets really unstable and I can just assume it's due to insufficient power.
  Running them with under clocked memory/default core/default voltage.
  Plan for 200-300 W for each card. I'd say that PSU can handle 3 5970s at stock settings, or 4 if you undervolt. Do you have a killawatt?  
						 | 
					 
					
						
							
							 
							
						 | 
					 
				 
			 |  
		 
	 | 
		
		
			
				
					
								
							crazyates
							
								Legendary 
								 
								  Offline
								Activity: 952 
								Merit: 1000
								 
								
								
								
								
								 
							 
						 | 
								
							
								  | 
								
												
												 June 25, 2012, 02:37:29 PM  | 
										  
								 | 
							  
									  
							What's the best brand for 5970 in terms of overclocking/Mhps?
  I got my Gigabyte 5870 to 450Mbps without much sweat, which is quite high for a 5870.
  But my Gigabyte 5970s can't seem to go post 700Mhps without freezing the whole system  :/
  I'm running them at 180/800MHz/Default voltage
  Mbps? You mean MH/s?    I kid... It's really card dependent. I like PowerColor, Sapphire, and Asus. A lot of people have good luck with Gigabyte. I've heard to stay away from XFX and Diamond, but again, YMMV. There is no BEST brand for OCing.  Also, while a 5970 is technically 2x 5870s in one card, the voltages are lower to keep the power/temps down. Stock voltage on a 5870 is 1.174, while stock voltage on a 5970 is 1.050. If you lowered your 5870 down to 1.05, you won't be getting 450MH/s.  If you raised your 5970 to 1.174, you MIGHT be able to get 400+ per core, but it would be a very bad idea. Power draw increases, temps become too much for the shared cooler, and your VRM temps would be through the roof. Not a good idea. Side note: Here are my 5870 speeds, for undervolting comparison: 460MH/s - 980/300/1.174 - My "all out" setting 425MH/s - 925/300/1.000 - My "max profit" setting 350MH/s - 755/300/0.950 - My "keep the temps down" setting. I think my card can get higher clocks at each voltages than average, so yours may be a little lower.  you should try higher at 0.950v...   mine has been stable for 200+ hrs at 830/195/0.950 the next step for me is 940/195/1.112 then 1010/195/1.175 it's xfx non-ref (hmm or maybe a sapphire non-ref...  haha) Mine's a PowerColor with a reference cooler, and it crashes at 775,300,0.95. I'm happy with 925,300,1.000, so that's what I leave it at most of the time.   
						 | 
					 
					
						
							
							 
							
						 | 
					 
				 
			 |  
		 
	 | 
	 |