Bitcoin Forum

Other => Beginners & Help => Topic started by: lueo on July 31, 2011, 10:48:42 PM



Title: PSU Watts for 6990*3 ?
Post by: lueo on July 31, 2011, 10:48:42 PM
Hi all,

I just got 3 ATI 6990. Since their Watts usages are very high, how much watts should the PSU have?

I've just thinking about a 1200 Watts PSU, but according to the wiki, should I buy a 1500-Watts one?

https://en.bitcoin.it/wiki/Mining_rig#Three_ATI_6990s.2C_Approximately_2.1_Ghash.2Fs


Title: Re: PSU Watts for 6990*3 ?
Post by: release on July 31, 2011, 11:26:47 PM
complete overkill. HCP 1200 should be plenty.


Title: Re: PSU Watts for 6990*3 ?
Post by: ManOfKnight on July 31, 2011, 11:31:28 PM
Holy crap...did you purchase that just for mining?  That is going to take a long time to pay back if you did.  I have been pricing just one 5830 and it will take about 120 days if you keep increasing the difficulty.


Title: Re: PSU Watts for 6990*3 ?
Post by: ManOfKnight on July 31, 2011, 11:32:52 PM
And so that I am not just a troll to your question...

There are numerous 1200 watt PSUs with HUGE amperage on the 12v rails...I would suggest the Corsair 1200w as it would more than keep your system up and running.


Title: Re: PSU Watts for 6990*3 ?
Post by: Sitarow on August 01, 2011, 02:29:24 AM
I am running at 1200 to 1250 watts with my rig.

And I use a 1250 OCZ one.

1500w is good when you start running 4 :)

PS.

When you have 3 phase and hitting close to 90amp each phase.

These 6990s are great to have. More GPU per system then going 4gpu setup.


Title: Re: PSU Watts for 6990*3 ?
Post by: lueo on August 01, 2011, 03:06:32 AM
Thanks guys, you're so kind.

Holy crap...did you purchase that just for mining?  That is going to take a long time to pay back if you did.  I have been pricing just one 5830 and it will take about 120 days if you keep increasing the difficulty.

That's just the reason why I purchase them for mining. I plan to use them for about 6 months and sell them in about 70% of the original value. I am pretty confident that I'll break even and even make a profit in this project.

I am running at 1200 to 1250 watts with my rig.

And I use a 1250 OCZ one.

1500w is good when you start running 4 :)

PS.

When you have 3 phase and hitting close to 90amp each phase.

These 6990s are great to have. More GPU per system then going 4gpu setup.

Good suggestion, thanks!

I am afraid of the overheating problem, so I just start to try from the 3 GPUs plan. 4 GPU sounds good... I'll take it into consideration for the next rig.

Could you suggest me a good motherboard for a 4 GPU plan? The motherboard I am using now only support 3 GPU (GA-790FXTA-UD5 with PCIex16 * 2, x8 * 1).


Title: Re: PSU Watts for 6990*3 ?
Post by: release on August 01, 2011, 03:43:32 AM
4 gpu motherboards are plentiful. The MSI gd70 890fx is a very popular one around bitcoin.