EVGA 850W BQ - Good Enough for 4 GPU?

[MrN1ce9uy]

I'm currently using an EVGA 850 B2 in a 4GPU rig, and have a EVGA 500B in a 1GPU rig, but I have another GPU coming to add to the 500B rig. I see the 850W BQ is cheaper on sale right now, but it's not as good as the B2 or B3. (Thinking about the future) Would you use it on a 4GPU mining rig? Or would you get a better quality power supply such as the 850 B3?

*Using RX 470, 480, 570, 580.

[QuintLeo]

I don't class the EVGA B3/G3/P3 series as worth even looking at.

 Their B2/G2/P2 series was quite good, but the newer series went to a JUNK SLEEVE BEARING DESIGN fan that is NOT going to last under the load a Cryptocoin mining rig puts on a power supply.

 I'd go for a G2 series for as long as you can find them (or the Seasonic X-series, ignore the Seasonic "Prime" series as they ALSO went to a bloody junk sleeve bearing fan in those).


 I'm not familier with the BQ at all (dunno if that series had a gold-rated varient).

[MrN1ce9uy]

I was JUST looking at the PSU Tier List Updated https://linustechtips.com/main/topic/631048-psu-tier-list-updated/ and noticed the B3 was down a tier from the B2. Thanks for pointing that out.  

What if I decided on the EVGA 1000W GQ? It's the Gold rated variant of the BQ I believe. It's on tier 2 with the B2. It's on sale for the same price as the 850W G2.

*I just found where the 850 BQ uses a Teflon nano-steel bearing in the fan, says it's better than a sleeve bearing.
**The 1000 GQ uses a Fluid Dynamic Bearing fan.

Are those types of bearings good enough for mining conditions, not as good as double-ball bearing I suppose?

[QuintLeo]

Never seen that "tier" thing before.

I'm going by the fact that I've NEVER had any sort of a "sleeve bearing" fan, no matter HOW fancy the name or how long the warrenttee on the PS was, last more than 2 years and usually they don't make it to 1 year before they die.

 Fluid Dynamic is a "sleeve bearing" fancy name.

 *ALL* of the fancy-name varients on a sleeve bearing claim to be better (the ones that use a "rifle" type slot IN the bearing do a better lube job than standard non-slotted types and a little better than a "straight slot" type, so technically they ARE better), but the seals STILL leak and the lube STILL runs out and the fan STILL dies way too soon.


 I'm not sure on the Teflon thing though - Teflon is VERY slick (though it's not THE slickest substance known to science any more, I think it's still #3 by a fairly narrow margin) and pretty bloody tough, so if they're using a Teflon coating to lubricate the sleeve bearing that MIGHT manage to last a long time - and it's definitely not going to leak, the only question there is how long it will take to wear down the Teflon.