• Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

will my psu handle an upgrade to crossfire?

Joined
Mar 31, 2007
Messages
1,895 (0.48/day)
Likes
162
Location
ontario canada
System Name home brew
Processor Intel Corei7 3770K OC @ 4.5Ghz
Motherboard ASUS P8Z77-V
Cooling Corsair H100
Memory 16GB DDR3 1600 GSKILL
Video Card(s) Powercolor Radeon 7970, MSI Radeon 7970
Storage Mushkin Chronos Deluxe 240gb. 2 TB Hdd.
Display(s) 3x24inch Dell Ultra IPS
Case CM storm trooper
Power Supply Antec Quattro OC ed. 1200w
Software Windows 7 Business x64
Benchmark Scores vantage: P43089
#1
Im considering of getting a 2nd 7970, as I ordered two 24' monitors for some triple screen gaming. pCARS is the main reason for that, which i should get around 30fps. But if i decide I want higher fps, not sure if my PSU will handle the load of the two graphics cards.

I ran fur mark the other day and my UPS reported a load of 400w. In compared to 200w when I was just playing diablo 3, and had a bluray playing on my other screen.

I looked at benches for the 7970 in crossfire, and the consumption under furmark was about 640w. With my 750w PSU, im un certain if that will do it. Just wanted some opinions.
 

de.das.dude

Pro Indian Modder
Joined
Jun 13, 2010
Messages
8,203 (2.95/day)
Likes
2,394
Location
Pune
System Name la de da... | Samsung NP355V5C-S05IN
Processor FX 8320 | AMD A8-4500
Motherboard ASRock 990FX Extreme 4 | Samsung something something
Cooling CM Hyper 212 EVO push:pull+ 1 panaflow 113CFM + 2 x 120mm NZXTs | Coolermaster Notepal
Memory 2x4GB DDR3 Corsair Vengeance 1600MHz CL9 | Samsunng 4GB + 2GB DDR3 1600MHz
Video Card(s) AMD 7790 GHZ edition! | 7670M + 7640G
Storage 1TB WD10EZEX | W.D 500GB Green AADS | Samsung 1TB
Display(s) dell S2240l 1080p IPS 21.5" | Samsung antiglare 15.6"
Case NZXT Guardian 921RB(@home) and Antec ASK4000B U3(Current)
Audio Device(s) Realtek ALC892 with THX True Studio | Realtek something
Power Supply Corsair GS600 | 90W Brick, 6 cell 48000mAh battery
Mouse Logitech G400, GOD TIER MOUSE!! LOGitech F310 gamepad!
Keyboard Logitech K200
Software Windows 8.1 x64 | Windows 8.1 x64
Benchmark Scores real men do bench presses not bench marks.
#2
hm... it should run. the max power draw for 7970s are 250W. so two would mean 500W or less.
add to that 125W for your overclocked cpu and you still have some power left. so i think it should run.
 
Joined
Apr 2, 2011
Messages
2,443 (0.98/day)
Likes
1,868
#3
Pushing it close, but within reason.

500 W - Crossfire GPUs
40 W - 2 HDDs
40 W - Fans and coolers
125 W - Mobo+CPU
705 W


It's close, but within reason. Most of the time the GPUs/CPU will be closer to idle, so the only time you should be worried is intense gaming.
 
Joined
May 14, 2009
Messages
2,132 (0.67/day)
Likes
477
Location
Chicago burbs
System Name Halloween Boo!
Processor Intel Core i7 3770K
Motherboard Gigabyte Z77-Up7
Cooling Custom Water/ Thermalchill TA 120.3/ Swiftech Apogeee XT/ MCP655/ Swiftech M icrores/ XSPC RX 240
Memory 16G G.Skill trident 2400MHz
Video Card(s) 3 x Radeon 7970
Storage OCZ Revo Drive 240G
Display(s) 24 inch Viewsonic
Case Phobia WayCoolIt Test Bench
Power Supply Nexus 1100 watt
#4
The answer is yes and no. If your overclocking, no. I just ran how many watts on a killowatt load meter with a 3770K overclocked to 4.7GHz and 2 x Radeon 7970's at 1200/1600 @1.2V and the reading was 775 watts gaming. If your not overclocking you will be relatively safe but I never like pushing PSU's over 90% to tell you the truth.
 
Joined
May 14, 2009
Messages
2,132 (0.67/day)
Likes
477
Location
Chicago burbs
System Name Halloween Boo!
Processor Intel Core i7 3770K
Motherboard Gigabyte Z77-Up7
Cooling Custom Water/ Thermalchill TA 120.3/ Swiftech Apogeee XT/ MCP655/ Swiftech M icrores/ XSPC RX 240
Memory 16G G.Skill trident 2400MHz
Video Card(s) 3 x Radeon 7970
Storage OCZ Revo Drive 240G
Display(s) 24 inch Viewsonic
Case Phobia WayCoolIt Test Bench
Power Supply Nexus 1100 watt
#5
hm... it should run. the max power draw for 7970s are 250W. so two would mean 500W or less.
add to that 125W for your overclocked cpu and you still have some power left. so i think it should run.


Your way off on your estimate. Way off.
 

Frick

Fishfaced Nincompoop
Joined
Feb 27, 2006
Messages
14,908 (3.43/day)
Likes
5,425
System Name A dancer in your disco of fire
Processor i3 4130 3.4Ghz
Motherboard MSI B85M-E45
Cooling Cooler Master Hyper 212 Evo
Memory 4 x 4GB Crucial Ballistix Sport 1400Mhz
Video Card(s) Asus GTX 760 DCU2OC 2GB
Storage Crucial BX100 120GB | WD Blue 1TB x 2
Display(s) BenQ GL2450HT
Case AeroCool DS Cube White
Power Supply Cooler Master G550M
Mouse Intellimouse Explorer 3.0
Keyboard Dell SK-3205
Software Windows 10 Pro
#6
Your way off on your estimate. Way off.
Nah it's pretty correct.

I would get a bigger PSU to be honest. I'm usually very conservative when it comes to PSU but in this case I'd get a new one. Especially if you're into overclocking.

Those 250Ws are during Furmark though.
 
Joined
Oct 29, 2010
Messages
2,944 (1.11/day)
Likes
1,379
System Name The Sheriff / The Deputy
Processor 2500K / G4560
Motherboard ASRock P67Extreme4 / Gigabyte GA-Z170-HD3 DDR3
Cooling CM Hyper TX3 / Intel stock
Memory 16 GB Kingston HyperX / 8 GB Kingston HyperX
Video Card(s) EVGA GTX 960 SSC / Gigabyte GTX 1050 Ti LP
Storage SSD, some WD and lots of Samsungs
Display(s) BenQ GW2470 / Samsung SyncMaster T220
Case Cooler Master CM690 II Advanced / Thermaltake Core v31
Audio Device(s) Asus Xonar D1/Denon PMA500AE/Wharfedale D 10.1/Senn HD518
Power Supply Corsair TX650 / Corsair TX650M
Mouse Steelseries Rival 100/ Mionix Avior 7000
Keyboard Sidewinder
Software Windows 10 / Windows 10 Pro
#7
At stock 2 x 7970 should work with that PSU under gaming load. If you plan to overclock (it is not a necessity since you will already have a a very powerful setup) then there might be a problem. Here's a power draw test with one card:

 
Joined
May 14, 2009
Messages
2,132 (0.67/day)
Likes
477
Location
Chicago burbs
System Name Halloween Boo!
Processor Intel Core i7 3770K
Motherboard Gigabyte Z77-Up7
Cooling Custom Water/ Thermalchill TA 120.3/ Swiftech Apogeee XT/ MCP655/ Swiftech M icrores/ XSPC RX 240
Memory 16G G.Skill trident 2400MHz
Video Card(s) 3 x Radeon 7970
Storage OCZ Revo Drive 240G
Display(s) 24 inch Viewsonic
Case Phobia WayCoolIt Test Bench
Power Supply Nexus 1100 watt
#8
At stock 2 x 7970 should work with that PSU under gaming load. If you plan to overclock (it is not a necessity since you will already have a a very powerful setup) then there might be a problem. Here's a power draw test with one card:

http://hardocp.com/images/articles/1327450545TTJicZSb5S_8_1.gif
I ran the power draw myself. Overclocked is much higher. 4.7GHz on a 3770K with 2 x Radeon 7970's @1200/1600(1.2 volts) draw max 775 watts. I don't know how else to explain it but I am overclocked on CPU too. Your chart is probably accurate with 1 card overclocked.

Nah it's pretty correct.

I would get a bigger PSU to be honest. I'm usually very conservative when it comes to PSU but in this case I'd get a new one. Especially if you're into overclocking.

Those 250Ws are during Furmark though.
No its not. I have the raw numbers. Furmark is weaK as Caldave responded in an earlier thread so I ran the draw test myself.
 
Last edited:

de.das.dude

Pro Indian Modder
Joined
Jun 13, 2010
Messages
8,203 (2.95/day)
Likes
2,394
Location
Pune
System Name la de da... | Samsung NP355V5C-S05IN
Processor FX 8320 | AMD A8-4500
Motherboard ASRock 990FX Extreme 4 | Samsung something something
Cooling CM Hyper 212 EVO push:pull+ 1 panaflow 113CFM + 2 x 120mm NZXTs | Coolermaster Notepal
Memory 2x4GB DDR3 Corsair Vengeance 1600MHz CL9 | Samsunng 4GB + 2GB DDR3 1600MHz
Video Card(s) AMD 7790 GHZ edition! | 7670M + 7640G
Storage 1TB WD10EZEX | W.D 500GB Green AADS | Samsung 1TB
Display(s) dell S2240l 1080p IPS 21.5" | Samsung antiglare 15.6"
Case NZXT Guardian 921RB(@home) and Antec ASK4000B U3(Current)
Audio Device(s) Realtek ALC892 with THX True Studio | Realtek something
Power Supply Corsair GS600 | 90W Brick, 6 cell 48000mAh battery
Mouse Logitech G400, GOD TIER MOUSE!! LOGitech F310 gamepad!
Keyboard Logitech K200
Software Windows 8.1 x64 | Windows 8.1 x64
Benchmark Scores real men do bench presses not bench marks.
#9
you are running those cards overclocked. he does not overclock his card. neither did he mention that they are GHz editions!

as i said, he will just about make it.
 
Joined
May 14, 2009
Messages
2,132 (0.67/day)
Likes
477
Location
Chicago burbs
System Name Halloween Boo!
Processor Intel Core i7 3770K
Motherboard Gigabyte Z77-Up7
Cooling Custom Water/ Thermalchill TA 120.3/ Swiftech Apogeee XT/ MCP655/ Swiftech M icrores/ XSPC RX 240
Memory 16G G.Skill trident 2400MHz
Video Card(s) 3 x Radeon 7970
Storage OCZ Revo Drive 240G
Display(s) 24 inch Viewsonic
Case Phobia WayCoolIt Test Bench
Power Supply Nexus 1100 watt
#10
you are running those cards overclocked. he does not overclock his card. neither did he mention that they are GHz editions!

as i said, he will just about make it.


You are correct about my cards are overclocked...... and if he does not overclock he is good 2 go but I just happened to run the draw from another thread so i thought I would post the results for him.
 
Joined
Nov 9, 2010
Messages
5,177 (1.97/day)
Likes
1,721
Processor Intel i7 950 @ 3.2GHz
Motherboard ASUS P6X58D-E
Cooling Corsair H50 push/pull
Memory Kingston HyperX 1600 8GB
Video Card(s) Sapphire HD 7970 OC
Storage Plextor M5P 128GB/WD Black 2x1TB,1x6TB/Seagate 1TB
Display(s) Panasonic TC-L32U3
Case Antec DF-85
Audio Device(s) Yamaha RX-V371 AVR
Power Supply XFX 850w Black Edition
Mouse Logitech G402
Keyboard Logitech K120
Software W10 Pro 64 bit
#11
Should be easily enough. 500w/30A for one 7970, and from what I've read the rec for two GPUs is 1.5 times the single rec, which is 750w/45A. That PSU puts out 60A.
 

Aquinus

Resident Wat-man
Joined
Jan 28, 2012
Messages
10,520 (4.81/day)
Likes
5,600
Location
Concord, NH
System Name Kratos
Processor Intel Core i7 3930k @ 4.2Ghz
Motherboard ASUS P9X79 Deluxe
Cooling Zalman CPNS9900MAX 130mm
Memory G.Skill DDR3-2133, 16gb (4x4gb) @ 9-11-10-28-108-1T 1.65v
Video Card(s) MSI AMD Radeon R9 390 GAMING 8GB @ PCI-E 3.0
Storage 2x120Gb SATA3 Corsair Force GT Raid-0, 4x1Tb RAID-5, 1x500GB
Display(s) 1x LG 27UD69P (4k), 2x Dell S2340M (1080p)
Case Antec 1200
Audio Device(s) Onboard Realtek® ALC898 8-Channel High Definition Audio
Power Supply Seasonic 1000-watt 80 PLUS Platinum
Mouse Logitech G602
Keyboard Rosewill RK-9100
Software Ubuntu 17.10
Benchmark Scores Benchmarks aren't everything.
#12
I don't have a 7970 but those numbers seem kind of high. 700-watts sounds like a max power draw under unusual circumstances. I have an i7 3820 (no stranger to eating electricity,) and two 6870s. Everything fully overclocked won't draw more than 500-watts off the wall (my UPS too has a kill-a-watt built in.) So I find it hard to believe that this will draw as much as you claim it to be unless IVB isn't as efficient as it has been claimed to be.

With all of this said: Even if I think that the two 7970s do run, you might be pushing your PSU kind of hard which will make temperatures go up, reliability go down, and it will reduce the life of your PSU as opposed to putting less load on it. You can't be too careful with PSUs because a bad PSUs can over volt your hardware if it can't draw enough current which could fry a lot of things on your motherboard.

The decision is up to you, but I personally wouldn't take the risk and I would get something a little bigger.
 

Bo$$

Lab Extraordinaire
Joined
May 7, 2009
Messages
5,626 (1.77/day)
Likes
971
Location
London, UK
System Name Desktop | Server
Processor Intel i7 2700k @ 4.4GHZ | AMD 5350 @ 2500MHZ
Motherboard Asus P7Z77-V Pro | Asus AM1I-A
Cooling GeLID Tranquilo | Stock Air
Memory Crucial Ballistix 2x8GB CL8 1600MHZ | Corsair Vengence 2x4GB CL9 1600MHZ
Video Card(s) Gainward GTX 780 Phantom GLH | PNY GTX 750Ti
Storage Samsung 840 EVO 250GB + 4TB WD Red | 2x Seagate Barracuda 2TB
Display(s) Samsung S27D390H + Asus VE276Q | Headless
Case Fractal Design R5 | CM Elite 110
Audio Device(s) Asus Xonar D1 w/Otone Stilo 5.1 and Creative Fatal1ty headset
Power Supply EVGA Supernova 850 G2| Corsair CX430M
Mouse Razer Imperator 2012
Keyboard Corsair K90
Software Windows 7 SP1 X64 | Ubuntu 16.04LTS
#13
you are fine
 
Joined
Mar 31, 2007
Messages
1,895 (0.48/day)
Likes
162
Location
ontario canada
System Name home brew
Processor Intel Corei7 3770K OC @ 4.5Ghz
Motherboard ASUS P8Z77-V
Cooling Corsair H100
Memory 16GB DDR3 1600 GSKILL
Video Card(s) Powercolor Radeon 7970, MSI Radeon 7970
Storage Mushkin Chronos Deluxe 240gb. 2 TB Hdd.
Display(s) 3x24inch Dell Ultra IPS
Case CM storm trooper
Power Supply Antec Quattro OC ed. 1200w
Software Windows 7 Business x64
Benchmark Scores vantage: P43089
#14
You are correct about my cards are overclocked...... and if he does not overclock he is good 2 go but I just happened to run the draw from another thread so i thought I would post the results for him.
It is standard clock speed in the video card. Typically in the past I didn't OC the video card, as it was usually a 1-2fps gain.

Seems the consensus is that Ill be fine. But with black friday coming up, ill look around for some deals for a new one.

Thanks all.
 
Joined
Mar 31, 2007
Messages
1,895 (0.48/day)
Likes
162
Location
ontario canada
System Name home brew
Processor Intel Corei7 3770K OC @ 4.5Ghz
Motherboard ASUS P8Z77-V
Cooling Corsair H100
Memory 16GB DDR3 1600 GSKILL
Video Card(s) Powercolor Radeon 7970, MSI Radeon 7970
Storage Mushkin Chronos Deluxe 240gb. 2 TB Hdd.
Display(s) 3x24inch Dell Ultra IPS
Case CM storm trooper
Power Supply Antec Quattro OC ed. 1200w
Software Windows 7 Business x64
Benchmark Scores vantage: P43089
Joined
Feb 7, 2009
Messages
620 (0.19/day)
Likes
156
Location
Michigan, USA
System Name Black Box
Processor Intel i7 3770K
Motherboard AsRock z77 Extreme 6
Cooling Thermalright Venemous X
Memory 2 x 8GB Crucial Ballistix
Video Card(s) 2 x GTX 480
Storage A-Data 128GB SSD, Samsung Spinpoint F3 1TB
Display(s) HANNspree 25" 1080p 2ms
Case Lian Li PC-9F
Audio Device(s) Creative XFI
Power Supply PC Power & Cooling Silencer MKII 750w
Software Win 7 pro x64
#16
Should be just fine. 7970's do seem to draw a lot of power, however, if you don't OC your cards you'll be fine. Also, keep in mind that furmark is not indicative of a typical load.