Do i need a new PSU?

[PredatorJ]

I am building a new conroe system and am interested in some opinions on a PSU for it.

I currently have an Enermax Liberty ELT500AWT powering my Athlon 64 x2 4400+ system with a single 7900 GTX and love it.

What I'm wondering is if this PSU will be enough for a new e6600, 7900 GTX SLI system.
New system would include the following:
e6600
Asus P5N32-SLI Premium
G.SKILL 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800
2x EVGA 7900 GTX 512
1x Western Digital Raptor WD740ADFD 74GB
1x Western Digital Caviar SE16 250GB 7200 RPM 16MB Cache SATA 3.0Gb/s Hard Drive
1x Pioneer DVR-110DBK Dual Layer Burner
Case= Thermaltake Tsunami Dream w/ 2 120mm Fans and 1 80mm

If the Enermax PSU would not be enough, which PSU should I go with?

I've considered the following PSU's,

OCZ GameXStream OCZ700GXSSLI ATX12V 700W Power Supply

PC Power & Cooling S61EPS EPS12V 610W

ENERMAX Liberty ELT620AWT ATX12V 620W

Corsair HX620w ATX12V v2.2 and EPS12V 2.91 620W Power Supply

Which one of these would be best? Any other Suggestions?

Thanks.

 

[davidhammock200]

Your 500W is a little light for highend SLI.

The Corsair 620W should be fine.

 

[jonnyGURU]

Don't 7900's actually use less power than 7800's and 6800's?

 

[Bbq]

Yea, in power consumption, it goes

6800 --> 7800 --> 7900
most------------------least

 

[PredatorJ]

According to this article...

NVIDIA's Tiny 90nm....

The 7900's draw less then the 7800's, but the 7900 GTX's draw more then the 7800,7900 and 7800 GTX, but less then the 7800 GTX 512's .


So overall it looks like my current PSU will be lacking?

And the Corsair 620 would be more than enough, including some headroom for future addons correct?

Thanks.

 

[davidhammock200]

According to this article...

NVIDIA's Tiny 90nm....

The 7900's draw less then the 7800's, but the 7900 GTX's draw more then the 7800,7900 and 7800 GTX, but less then the 7800 GTX 512's .


So overall it looks like my current PSU will be lacking?

And the Corsair 620 would be more than enough, including some headroom for future addons correct?

Thanks.

Correct!

Specs: http://www.corsairmicro.com/corsair/HX_power_supply.html

In theory up to 600W of +12V (50A), more like a combined +12V@40A+ in reality.

 

[PredatorJ]

Okay!

Thanks for all the help. I'm ordering the Corsair 620W.

 

[dBTelos]

I would think that a HX520 would provide enough power considering that it has nearly 500W on the 12V rail alone. The HX620 should be good through quad-sli DX10 though

 

[davidhammock200]

I would think that a HX520 would provide enough power considering that it has nearly 500W on the 12V rail alone. The HX620 should be good through quad-sli DX10 though

Think about it, it is a 520W PSU, so it can't really have 500W on the +12 rails, 420W's maybe, which would be +12V@35A.

Just as the 620W, can't really gave 600W on the +12V rails,
but it probably can have 520W, which is +12V@43A.

These are both great PSU's, now they need to tighten the QC & get rid of the buzzing.

 

[dBTelos]

Think about it, it is a 520W PSU, so it can't really have 500W on the +12 rails, 420W's maybe, which would be +12V@35A.

Just as the 620W, can't really gave 600W on the +12V rails,
but it probably can have 520W, which is +12V@43A.

Hmm.

 

[jonnyGURU]

These are both great PSU's, now they need to tighten the QC & get rid of the buzzing.

Yours is buzzing?

 

[davidhammock200]

Hmm.

Think about it, it is a 520W PSU, so it can't really have 500W on the +12 rails, 420W's maybe, which would be +12V@35A.

Just as the 620W, can't really gave 600W on the +12V rails,
but it probably can have 520W, which is +12V@43A.

Don't believe everything you read, THINK!

 

[jonnyGURU]

You can do it, Dave.

If you just had one HDD and one optical, you could do it because your 3.3V and 5V loads will be really low.

When I did the crossload test on the Corsairs I had the 12V rails maxed out and everything stayed within spec.

 

[davidhammock200]

You can do it, Dave.

If you just had one HDD and one optical, you could do it because your 3.3V and 5V loads will be really low.

When I did the crossload test on the Corsairs I had the 12V rails maxed out and everything stayed within spec.

Any real PC that can put a 30A+ load on the +12V, is going to consume more than 20W on the +5 & +3.3 combined.

 

[dBTelos]

Any real PC that can put a 30A+ load on the +12V, is going to consume more than 20W on the +5 & +3.3 combined.

Not really... many people have gaming systems with nothing but the main gaming componants that put load on the 12v rail and a single HD.