290 vs 290x 2 card system on 1000w psu possible?

[BitCoinPokerBro]

After first reading about this card on a scrypt mining blog stating power usage was 300-350w with a kh/s rate of 800-+950 I began searching the web for good deals to purchase 2 cards. Having already purchased a brand new coolmaster 1000w (80 plus gold certified) power supply a few months ago that needed to be put to use I'd rather not have to upgrade since it hasn't even accumulated 4 weeks of run time under vary low load (1x saphire 6970) for about 8-12 hours a day.

Are these estimates both power usage and kh/s ratings accurate?

If memory serves correctly both 290 and 290x have a manufacturer stated requirement of 600-650w. Although that can't be right because so many miners run 4 cards on one psu.

So basically what I want to know is if 2 R9 290x's or 290's can run on a 1000w system.

Current Specs-

Rosewill Thor case
MSI Z77A-G45 Motherboard -2 double spaced pci-e slots and 1 single spaced
8Gigs Ripjaw serries DDR3 Ram
Intel I3 dual core processor 2100 series
Western Digital 2TB hard drive with 64mb cache
CoolMaster 1000w modular PSU
1x Sapphire 6970 - @ 275-325 kh/s (hoping for 4-5x current min kh/s)

Originally built as a gaming/personal pc/part time mining type system so I spent more on things that wouldn't necessarily be needed for mining.

As a side note regarding cases. The huge fans and triple inside volume really help keep the video card cool. That and the side panel/top of the rosewill thor is perforated/vented for maximum airflow. Compared to what the 6970 sounded like in a normal store bought pc case it's practically silent. Totally worth the added expense for a multipurpose machine. Other full size cases designed for gaming with extra venting and perforated side panels would probably be just as good or better though.

[greghawk]

I have a noname 1200W PSU 80bronze and 3 290X (one with Powered Riser) and the System uses 1120W in total. The cards doing fine with 885kh/s at 60grad celsius.
When starting up the system uses 150W.

So I think it should work.

[TookDk]

I have a noname 1200W PSU 80bronze and 3 290X (one with Powered Riser) and the System uses 1120W in total. The cards doing fine with 885kh/s at 60grad celsius.
When starting up the system uses 150W.

So I think it should work.

I agree, the manufacturers are conservative with the spec (which is good).

I run MSI R9 280X, which is specified for 375W on 12V.
With default volting it draws 300W on the 12V at full hashing, with undervolting its 270W.

One more comment; bronze rated PSU has typical less efficiency at full load, as little as 80 % efficiency, maybe that is worth taking into consideration if you pay for your own electricity. That is 200W wasted, unless you use your rig to heat the house

[BitCoinPokerBro]

I have a noname 1200W PSU 80bronze and 3 290X (one with Powered Riser) and the System uses 1120W in total. The cards doing fine with 885kh/s at 60grad celsius.
When starting up the system uses 150W.

So I think it should work.

Exactly the type of comment I was hoping for. Thank you so much

[thevwu]

Currently running 3 R9 290s with an Evga Supernova.  They seem to crash at a traditional 1000/1500 overclock though, I can only go to 947/1450.  Drops about 90 kh/s in total.  So if 3 R9 290s can run with a mild throttle, then 2 290s definitely can.

[DirkDunkirk]

Currently running 3 R9 290s with an Evga Supernova.  They seem to crash at a traditional 1000/1500 overclock though, I can only go to 947/1450.  Drops about 90 kh/s in total.  So if 3 R9 290s can run with a mild throttle, then 2 290s definitely can.

i got my two 290x's to run at 888 / 1500 - do you think I could add 2 more with an EVGA platinum 1000psu?

[TookDk]

Silly you