Is 620w enough for SLi

Had3s · 6 Jan 2007 at 13:19

Would my PSU handle another G80? I've read that the PCI-E supply 75w, alongside 2x75w for each card = 450w (maxxed out). Add onto that a Conroe, chipset, ram, fans and drives. Would I be struggling?

thefishdude · 6 Jan 2007 at 13:20

http://www.slizone.com/object/slizone_build_psu.html#certified_powersupplies

LoadsaMoney · 6 Jan 2007 at 13:25

Id say no way, your talking about Enermax 1000w for GTX SLi.

Had3s · 6 Jan 2007 at 13:28

They have an Antec Truepower Trio there rated at 650w for SLi. I think my PSU could possibly handle it when idle, but would pop when any stress was put on the gfx.

Raikiri · 6 Jan 2007 at 13:31

Don't think it would work, but then I also don't think you need a 1000w PSU, the 850w enermax or 850w etasis would be plenty.

jaykay · 6 Jan 2007 at 13:32

thats for dual gts or 7950gx2
i would say your pushing it for sli any way why do u need that much power

dmsims · 6 Jan 2007 at 13:32

should have read the specs !

Had3s · 6 Jan 2007 at 13:35

I don't. I'm just inquisitive for future reference.

jaykay · 6 Jan 2007 at 14:05

lol any way best get a 750w minium or a 800w-850w to be sure

Jonny L · 6 Jan 2007 at 14:09

^^^ what he said, isn't your cpu holding the gtx back a bit?

thefishdude · 6 Jan 2007 at 14:14

list of compatable psu are in my link in my first reply but basically its 650min gts sli and 750 min gtx sli

fornowagain · 6 Jan 2007 at 14:35

thefishdude said:
list of compatable psu are in my link in my first reply but basically its 650min gts sli and 750 min gtx sli

The overall wattage is meaningless. The only value that counts is the combined 12v. In the case of the Antec its a massive 52A (60A with the GTX mentioned). Don't go assuming 650W is a GTS SLi minimum, it not.

Raikiri · 6 Jan 2007 at 14:38

But is isn't 52a, the value given per rail is the maximum it can supply on it's own.

If it were 52a then that would mean 624w, more than the PSU is rated for including the 5v and 3v rails.

fornowagain · 6 Jan 2007 at 14:39

Raikiri said:
But is isn't 52a, the value given per rail is the maximum it can supply on it's own.

If it were 52a then that would mean 624w, more than the PSU is rated for including the 5v and 3v rails.

http://www.antec.com/us/productDetails.php?ProdID=23650

* +12V1, 12V2,12V3 maximum output 624 Watts max.

Taking each rail would sum to 57A/684w, its not. You can only go by the specs. Each rail can supply up to 19A, just not all at the same time.

Same on the 750W mentioned.

http://www.silverstonetek.com/products-75zf.htm

combined +12V 60A/720W

Had3s · 6 Jan 2007 at 14:46

This is why it's been confusing me. Generally I thought it would be down to amperage.

fornowagain · 6 Jan 2007 at 14:52

Had3s said:
This is why it's been confusing me. Generally I thought it would be down to amperage.

It is, so to answer your original question. An Enermax Liberty supplies 36A@12V and doesn't really have enough for SLi G80.

Had3s · 6 Jan 2007 at 15:32

Sold it and gonna get the 850w or 1000w. It was either that or wham another PSU in the case (or perch it on top)*

Robert · 6 Jan 2007 at 15:58

LoadsaMoney said:
Id say no way, your talking about Enermax 1000w for GTX SLi.

Er, what? I'd say enermax 850 would EASILY cope with GTX sli.

sablabra · 6 Jan 2007 at 16:04

I just ordered corsair hx620w, and I'd be surprised if it doesn't handle 8800gtx sli. Each card draws about 150w and about 200w for cpu + mobo + hdd etc. That's 500w, and it can supply 50A, or 600w, on the 12V rail. I remember jonnyguru tested it with 40A from one connector without any problems whatsoever.
PS: I will only use one 8800gtx

I wouldn't recommend enermax galaxy because of the 5V and 3.3V ripple during high load on 12V rails.

vairo · 6 Jan 2007 at 16:30

Er, what? I'd say enermax 850 would EASILY cope with GTX sli.

wow didnt know u can get more than 800 :eek: