A little help need on psu and 2900

skunksta · 8 Jul 2007 at 20:55

Ok i got a Enermax Liberty 500W ELT500AWT ATX2.2 Modular SLI Compliant PSU
and can but dont want to upgrade due to rebuild of case or close to.Got my C2D clocked to 2.8 (at the mo) only 2 gig of ram and i got a 850 PE in it at the mo with no problems but want to buy a 2900 tomorrow as its on offer this week the 512 one btw .will i be needing to upgrade the psu? .

And yes before anyone says why dont u get the gts 640mb one .well it was a close thing but i picked the 2900 mad or not thats the way i am going.

Thanx in advance for any info. (think it will be but want to be 100%)

No plans on over clocking the card i dont like the prettys just the fps in online.
setting turned down no footsteps in cod2 over 500 fps etc

Cyber-Mav · 8 Jul 2007 at 20:57

if your mind is set on a 2900 then just go buy it. if your psu blows up then just get another psu.

skunksta · 8 Jul 2007 at 20:58

Cyber-Mav said:
if your mind is set on a 2900 then just go buy it. if your psu blows up then just get another psu.

LoL thanks i guess ?

Cyber-Mav · 8 Jul 2007 at 21:01

dunno what more to say really. i mean if your dead set on getting the card then don;t let anything set you back.

a 8800gts is guaranteed to work fine with your current psu. but since you don't want that card then your only option is to get the 2900 and sty it out with your current psu. if you get problems then you got to get a new psu. no way around it if your dead set on the 2900.

i personally would look at the cost of a 2900+ a new psu which = around the price of a 8800gtx which will work fine with your current psu. but thats the price you pay if you stick preference to a single brand.

Margaret · 8 Jul 2007 at 21:14

You can try it, I doubt an Enermax will just blow and take stuff out with it.

Perhaps have a Google around and see if anyone else is managing it.

LoadsaMoney · 8 Jul 2007 at 21:18

Id say your psu will be fine, 384w (32a) for the 12v rails, 2900 only uses about 348w underload on a full system according to anandtech's review, id await more opinions though.

Cyber-Mav · 8 Jul 2007 at 21:22

if its got 384w on the 12v rails then its more than up to the job. tomnbk is running his on a hiper 580 which has 360w on the 12v rails.

skunksta · 8 Jul 2007 at 21:26

Thanks for the input after looking ABIT i cant see why it would not be upto it but mav had me aittle worried there.Will wait and see some more replys if i get any

Margaret · 8 Jul 2007 at 21:27

LoadsaMoney said:
Id say your psu will be fine, 384w (32a) for the 12v rails

I didn't know it would be calculated like that, think that's put my worrying at an end too then. (500w with 2 18a rails)

Edit: Yep I just found it can supply a total of 36A on the 12v lines.

Finally my mind is at rest.

fornowagain · 8 Jul 2007 at 21:42

Jihad said:
I didn't know it would be calculated like that, think that's put my worrying at an end too then. (500w with 2 18a rails)

Edit: Yep I just found it can supply a total of 36A on the 12v lines.

Calculated like what? The Enermax has 2 x 22A rails with a combined 12v wattage of 384W/32A. Its got nothing to do with the psu overall wattage, they all have different power distributions to the rails. You had the Akasa? That's a very different beast, much smaller 12v rails, 24.1A/290W.

And you can't just add the rails together, if you could it would be a 700W psu

Margaret · 8 Jul 2007 at 22:07

fornowagain said:
Calculated like what? The Enermax has 2 x 22A rails with a combined 12v wattage of 384W/32A. Its got nothing to do with the psu overall wattage, they all have different power distributions to the rails. You had the Akasa? That's a very different beast, much smaller 12v rails, 24.1A/290W.

And you can't just add the rails together, if you could it would be a 700W psu

Ugh I really hate working stuff out with PSU ratings!

All I'm reading is:

Both state that they can supply a total of 36A on the 12V line(s), which is where most of the load will come from.

From a certain .net site that can't be linked on this forum.

LoadsaMoney · 8 Jul 2007 at 22:14

Yeah if combining was like that, then the Enermax could do 44a, as each 12v rail is 22a, but it doesn't work like that as said above.

skunksta · 8 Jul 2007 at 22:19

So looking good for the straight swap and driver clean up thanks again guys.Kinda new it would be but its nice to have people confirm it.

Margaret · 8 Jul 2007 at 22:21

LoadsaMoney said:
Yeah if combining was like that, then the Enermax could do 44a, as each 12v rail is 22a, but it doesn't work like that as said above.

For the love of god I'm still confused.

A guy on the nZone forums is running a 8800GTX from a "Akasa 500W Dual 12v rail PSU" fine he says. (Guessing that's more orl ess the same as my PSU, sounds it)

Meh I guess I'll have to just pray it works fine.

Kinda wish I waited to test the GTX first before buying another hard drive.

fornowagain · 8 Jul 2007 at 22:28

Jihad said:
For the love of god I'm still confused.

A guy on the nZone forums is running a 8800GTX from a "Akasa 500W Dual 12v rail PSU" fine he says. (Guessing that's more orl ess the same as my PSU, sounds it)

Meh I guess I'll have to just pray it works fine.

Kinda wish I waited to test the GTX first before buying another hard drive.

What's to be confused about? You already posted a pic of the power supply.

Some manufacturers are up front and tell you the combined 12v power. Some obfuscate the values. I've done this a while, so I can estimate the 12V combined from the size of the two other rails. In your case I don't need to because they tell you in a sneaky way.

Your 12v is 500-210 = 290W or 24.1A its as simple as that.

Margaret · 8 Jul 2007 at 22:30

fornowagain said:
Your 12v is 500-210 = 290W or 24.1A its as simple as that.

Ahh now I see.

That settles it then, I'm screwed.

fornowagain · 8 Jul 2007 at 22:36

Jihad said:
Ahh now I see.

That settles it then, I'm screwed.

I don't know about that, Tom's using about 300W at 12v with an XT. The GTX uses less, you might just get away with it. As I said before monitor the rail voltages with a multimeter. If it runs and the psu doesn't get too hot, check the voltages are holding and you should be ok. Just don't run it overloaded. Personally I'd want some peace of mind and buy a Corsair and be done with with it, but hey.

Margaret · 8 Jul 2007 at 22:38

fornowagain said:
I don't know about that, Tom's using about 300W at 12v with an XT. The GTX uses less, you might just get away with it. As I said before monitor the rail voltages with a multimeter. If it runs and the psu doesn't get to hot, check the voltages are holding and you should be ok. Just don't run it overloaded.

Ah actually yes! I remember seeing an article where a X1950-XTX used something like 308W, and the GTX used about 321W, and that was on a quad core system.

I'll have a look how it looks on the multimeter on tuesday.

skunksta · 9 Jul 2007 at 15:20

Well comes tomorrow my blow heater (2900) .

skunksta · 10 Jul 2007 at 09:02

OMG it just came.Its the size of a house brick from my 850 PE (which i thought was big) to this monster.Big step up hope i see it in fps to.And dont wish i got the gts but as i said i am a online gamer and the pretty's always get turned down to make the player stand out as much as poss. And as it was cheaper than the cheapest gts 640 (£20-25) if i get 10 fps less in some games than the gts i dont mind one bit.