Go Back   AnandTech Forums > Hardware and Technology > Power Supplies

· Hardware and Technology
· CPUs and Overclocking
· Motherboards
· Video Cards and Graphics
· AMD Video Cards
· Nvidia
· Displays
· Memory and Storage
· Power Supplies
· Cases & Cooling
· SFF, Notebooks, Pre-Built/Barebones PCs
· Networking
· Peripherals
· General Hardware
· Highly Technical
· Computer Help
· Home Theater PCs
· Consumer Electronics
· Digital and Video Cameras
· Mobile Devices & Gadgets
· Audio/Video & Home Theater
· Software
· Software for Windows
· All Things Apple
· *nix Software
· Operating Systems
· Programming
· PC Gaming
· Console Gaming
· Distributed Computing
· Security
· Social
· Off Topic
· Politics and News
· Discussion Club
· Love and Relationships
· The Garage
· Health and Fitness
· Home and Garden
· Merchandise and Shopping
· For Sale/Trade
· Hot Deals with Free Stuff/Contests
· Black Friday 2015
· Forum Issues
· Technical Forum Issues
· Personal Forum Issues
· Suggestion Box
· Moderator Resources
· Moderator Discussions

Thread Tools
Old 12-31-2011, 12:29 AM   #1
Diamond Member
RaistlinZ's Avatar
Join Date: Oct 2001
Location: Virginia, USA
Posts: 7,423
Arrow How large PSU for 7970 CrossFire?

I currently have a Corsair HX750 PSU. I'm sure 7970 CrossFire would be pushing it with this, but how large of a PSU would I need?
i7-5820K @ 4.4GHz l ASUS X99-PRO l MSI Gaming GTX 980Ti l 16GB PC2800 l 500GB Saumsung 850 EVO l Corsair HX750 l Corsair H110 l Jonsbo W2 Case l Dell U3011
RaistlinZ is offline   Reply With Quote
Old 12-31-2011, 01:21 AM   #2
Diamond Member
RavenSEAL's Avatar
Join Date: Jan 2010
Location: Mejico
Posts: 8,671

You should be fine but I guess if you REALLY wanna be safe, around 900w should be the mark.
AMD X6 1090T @ 3.8GHz Cooled by CM Hyper212+ P/P | Sapphire AMD HD6870 Vapor-X Crossfire @ 930/1150 | Gigabyte 990XA-UD3 | 8GBs Patriot G2 DDR3-1600Mhz | Corsair FORCE 3 90GB SSD | 1TB WD RAID0 | Antec HCG-750 | CM HAF 932

Lonely HeatWare

RavenSEAL is offline   Reply With Quote
Old 12-31-2011, 02:08 AM   #3
Junior Member
Join Date: Dec 2011
Posts: 1

7970 requires less power than a 570, so CF 7970 on corsair HX 750w will work fine
Satire is offline   Reply With Quote
Old 12-31-2011, 07:58 AM   #4
lehtv's Avatar
Join Date: Dec 2010
Posts: 11,026

Will work fine on a 750W corsair. 200W per card + 200W for the rest of the system (OC'd i7) ~ 600W/750W ~ 80% at full system load which is fine. Corsairs are designed to handle that sort of load without issues.
lehtv is offline   Reply With Quote
Old 12-31-2011, 12:32 PM   #5
BoomerD's Avatar
Join Date: Feb 2006
Location: Where I hang my hat.
Posts: 46,381


Our test system is based on a power hungry Core i7 965 / X58 system. This setup is overclocked to 3.75 GHz. Next to that we have energy saving functions disabled for this motherboard and processor (to ensure consistent benchmark results). On average we are using roughly 50 to 100 Watts more than a standard PC due to higher CPU clock settings, water-cooling, additional cold cathode lights etc.

We'll be calculating the GPU power consumption here, not the total PC power consumption.

Measured power consumption

System in IDLE = 163W
System Wattage with GPU in FULL Stress = 355W
Difference (GPU load) = 192W
Add average IDLE wattage ~3W
Subjective obtained GPU power consumption = ~ 195 Watts
Mind you that the system wattage is measured at the wall socket.
BoomerD is offline   Reply With Quote
Old 01-05-2012, 03:51 PM   #6
VC&G Moderator
Elfear's Avatar
Join Date: May 2004
Posts: 6,375

As long as you're not overclocking the cards much you should be fine. I was getting random shut-downs with the parts in my sig (cards were overclocked) on a quality 800W PSU. That happened playing Starcraft II and sometimes running through the STALKER: COP benchmark. My Kill-O-Watt indicated 770W at the wallplate. A new 1000W PSU solved the issue.
4770k | Maximus VI Hero | EVGA 980Ti | 16GB DDR3 | Custom H20
Elfear is offline   Reply With Quote
Old 01-05-2012, 04:15 PM   #7
Senior Member
Join Date: Nov 2005
Posts: 951

If you are going to OC and OV the cards and run them 100% folding or something like that and run your CPU 100% folding as well then I'd go at least 850w. If you are just gaming then your 750 will be just fine.
5820K@4.4ghz|MSI X99S SLI Plus|32gb G.Skill 3200|Titan X SLI|1TB Samsung SSD|ASUS ROG Swift G-Sync LCD|Corsair AX1200
DooKey is offline   Reply With Quote

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 05:06 AM.

Powered by vBulletin® Version 3.8.8 Alpha 1
Copyright ©2000 - 2015, vBulletin Solutions, Inc.