750W PSU enough for 2 R9 290 Tri-X @ Stock with this system?

Hobiehomecat

Reputable
Jul 14, 2014
11
0
4,510
System Specs:

Case: CORSAIR, Carbide Series® SPEC-03 Red LED Black Mid-Tower Computer Case, ATX / mATX / mini-ITX, No PSU, Steel/Plastic

PSU: THERMALTAKE, TPD-0750 Toughpower™ Gold 750W Power Supply w/ Modular Cables, 80 PLUS® Gold, 24-pin ATX12V EPS12V, 4x 8/6-pin PCIe, Retail

MOBO:MSI, Z87M-G43, LGA1150, Intel® Z87, DDR3-3000 (O.C.) 32GB /4, PCIe x16, SATA 6Gb/s RAID 5 /6, DP + HDMI + DVI + VGA, USB 3.0 /2+2, HDA, GbLAN, mATX, Retail

CPU:INTEL, Core™ i5-4670K Quad-Core 3.4 - 3.8GHz TB, HD Graphics 4600, LGA1150, 6MB L3 Cache, DDR3-1600, 22nm, 84W, EIST VT-x XD, Retail

CPU FAN: ARCTIC, Freezer 7 Pro Rev.2 CPU Cooling Fan, Socket
1150/1155/1156/1366/775/939/AM2/AM3, 127mm Height, Retail

RAM
: CORSAIR, 8GB (2 x 4GB) Vengeance™ LP PC3-12800 DDR3 1600MHz CL9 (9-9-9-24) 1.5V SDRAM DIMM,

GPU: Non-ECC SAPPHIRE, Radeon™ R9 290 Tri-X OC (UEFI) 1000MHz, 4GB GDDR5 5200MHz, PCIe x16 CrossFire, DP + HDMI + 2x DVI, Retail

SSD:CRUCIAL, 512GB MX100 SSD, MLC Marvell 88SS9189, 550/500 MB/s, SATA 6 Gb/s, 2.5-Inch, 7mm w/ 9mm Adapter, Retail

DVD Player:LITE-ON, iHAS124-14 Black 24x DVD±RW Dual-Layer Burner, SATA, OEM

I measured the total system power consumption while running 3DMark's Firestrike using Kill a Watt from the wall and it topped out at about 320 Watts, ran Star Citizen at ultra(basically Crysis 3) and it ran at about the same under 100% load for the GPU and something like 85% for the CPU. Max temp under Furmark for the GPU was 80C and like 50C for the CPU but with fans on automatic and only at ~35-50%. If I add another Sapphire R9 290 Tri-X, will I still be safe power wise if I keep them at stock?
 

Hobiehomecat

Reputable
Jul 14, 2014
11
0
4,510
Suztera, can you explain to me why I would need 850w? If my total system wattage is only 320 @ 100% GPU load and like 85% CPU load, that still leaves my PSU with like 430 watts until I hit its rated power supply.
 

viewtyjoe

Reputable
Jul 28, 2014
1,132
0
5,960


AMD recommends at least 800w for SLI 290s, but you can probably scrape it with 750w. It seems kind of silly to go a little cheaper on something as important as the PSU when the chip manufacturer says to go higher.
 


How much do you need for a single card then ? 650W should be enough?
 


Some 550W can be done with a single R9 290 but they are the really top end 550W psu. 650W is enough for a R9 290.
 
You're not at 100% load till running furmark and prime 95.

Real Hard Tech recommends a 1000W power supply to run a pc with 2 x r9 290's.

Get one from tiers 1, 2a or 2b of http://www.tomshardware.com/answers/id-1804779/power-su...

eg EVGA Supernova 1000W http://www.newegg.com/Product/Product.aspx?Item=N82E168...
 

paopaw07

Honorable
Nov 27, 2013
67
0
10,640
I've tried running Crossfire R9 290 Tri X sapphire on my Seasonic x750 Gold. So far so good. I don't experience any troubles right now. It's been a week since I crossfire my R9 290. But I bought a Seasonic X1050 80 plus gold just incase.