24-pin-vs-20-pin-psu for a new build?

[rpf717rpf]

I'm building the following system for a HTPC:

GIGABYTE GA-965P-DS3 Rev. 3.3 LGA 775
E6600 Core Duo
8600 ish nVidia GPU (when they come out)
2gb Corsair ddr2 800 ram
Some old IDE hard drive

I have a "silent" PSU on the existing system that I really like (its quiet and as a knob for the fan so I can set the speed where I want), however its the 20 pin connector type (old style) versus the new 24 pin.

I've read confusing things about compatability of the 20pin PSU's in 24pin Motherboards. I've been using it in a 24 pin ECS board for about a year with no problems. However, with my new system would it be ok for me to use my old PSU?

Thanks

 

[John]

Originally posted by: rpf717rpf
However, with my new system would it be ok for me to use my old PSU?

Not necessarily. Post the brand and model and we'll go from there.

 

[Aluvus]

Originally posted by: rpf717rpf
I'm building the following system for a HTPC:

GIGABYTE GA-965P-DS3 Rev. 3.3 LGA 775
E6600 Core Duo
8600 ish nVidia GPU (when they come out)
2gb Corsair ddr2 800 ram
Some old IDE hard drive

I have a "silent" PSU on the existing system that I really like (its quiet and as a knob for the fan so I can set the speed where I want), however its the 20 pin connector type (old style) versus the new 24 pin.

I've read confusing things about compatability of the 20pin PSU's in 24pin Motherboards. I've been using it in a 24 pin ECS board for about a year with no problems. However, with my new system would it be ok for me to use my old PSU?

Thanks

20-pin supplies are completely fine for use with 24-pin motherboards, but cannot always keep up with the 12 V rail power demands of modern computers. What make and model is your current supply?

 

[rpf717rpf]

Ok here's the PSU
Its an FSP 350watt

Output

Output Voltage Min. load Max. load Load Reg. Ripple & Noise
+5Vsb 0.0A 2.0A ±5% 50mV P-P
-5V 0.0A 0.3A ±10% 100mV P-P
-12V 0.0A 0.8A ±10% 120mV P-P
+12V 0.2A 16.0A ±5% 120mV P-P
+5V 1.0A 30/25.5A ±5% 50mV P-P
+3.3V 0.3A 21.2/28.0A ±5% 50mV P-P


?+3.3V & +5V total output not exeed 220W
?+3.3V & +5V & +12V total output not exeed 300W


Using this calculator

I come up with an approximate wattage requirement of 280ish for my new system - its pretty light on components (I selected the 8800gts as my card since I'm sure the 8600 series will be less power hungry than these).

Thanks!

 

[betasub]

I have this FSP PSU, and although it's worked fine with various systems with older graphics cards (FX5900, 6600GT) it doesn't provide enough juice to boot the same systems with an x1800xt, so it's equally unlikely to be able to drive an 8800GTS.

 

[rpf717rpf]

Originally posted by: betasub
I have this FSP PSU, and although it's worked fine with various systems with older graphics cards (FX5900, 6600GT) it doesn't provide enough juice to boot the same systems with an x1800xt, so it's equally unlikely to be able to drive an 8800GTS.

Well I definitely won't be running a 8800gts (I assume the 8600 series will be similar watts but a bit less), but even if i were, the PSU calc as above, states my peak wattage would be 280, which seems well below 350. Am I missing something?

 

[Captante]

Yes ... you are missing the fact that your PSU has lost a considerable amount of its original power output over time... also the most important spec for new PC's is the amp-rating of the +12v rail & 16 amps total just isn't going to get it done with a mid/high end GPU.

Frankly considering how many decent PSU's in the 450-500 watt range can be had for less then $75, I can't understand why you would even consider spending a bunch of cash on nice components & then skimp out on the most important component of your new system.

 

[rpf717rpf]

"I can't understand why you would even consider spending a bunch of cash on nice components & then skimp out on the most important component of your new system"

Thats the same argument that salesmen use to sell you $100 monster cables for your new TV.

$70 is $70, and if I already own something that would work fine I'd just as soon use that.

Its not that i was making a concious decision to "skimp". I wasn't aware that it was "skimping" or else I wouldn't be asking the question, right? Frankly, it seems a reasonable thought. After all 280 < 350. Thanks for the input.

 

[Captante]

While I understand the point you are trying to make it just doesn't add up because even if you spend only $700 building your new system, thats still ten times the price of an adequate psu. (& 5 times the price of a high end model) Considering that if your current 350 watt FSP blows up under heavy load it could easily take some of your new stuff along with it when it goes I'd say its just not worth the risk.

In any case sorry if I seemed a bit harsh!

 

[rpf717rpf]

no prob,

now to find a good deal on a quiet ~500ish watt PSU

 

[Aluvus]

Originally posted by: rpf717rpf

Well I definitely won't be running a 8800gts (I assume the 8600 series will be similar watts but a bit less), but even if i were, the PSU calc as above, states my peak wattage would be 280, which seems well below 350. Am I missing something?

The "calculators" provide an (often very rough) estimate. And more importantly, they typically only spit out a total wattage estimate, not accounting for how the total power draw is distributed among the various rails.

For instance, your supply is rated to a total output of 350 W. But only 16 A of that (192 W) can be on the 12 V rail. By way of comparison, manufacturers suggest 28 A on the 12 V rail for systems with some GeForce 8800 cards (note again that this is just a rough estimate on their part).

I don't know what power requirements for the GeForce 8600 are supposed to be like, but it seems to me that your current supply would be a bit stretched to pull it off.

 

[Teclis2323]

there's a difference between someone recommending $100 spent on cables for pure margin profits and someone recommending $100 on the power-supply in your new computer.

If cables break, you buy new cables.

If your PSU blows, you buy new lots of things.

 

[rpf717rpf]

Originally posted by: Teclis2323
there's a difference between someone recommending $100 spent on cables for pure margin profits and someone recommending $100 on the power-supply in your new computer.

Sigh . . .

You're missing my point, I'm not saying its not good advice. On the contrary I'm shopping for a Corsair HX520W as we speak (seems like a good model for my needs right?)

My point is that I won't blindly spend an extra 10% for my "system" just because I'm "already spending 90% . . so what's another 10%"? I will, however, happily pay that 10% if I need to, which in this case it seems I do. Now I know, and "knowing is half the battle" Make sense?

Anyhow to stay on subject: the Corsair HX520W has gotten good reviews, and has the following specs:

9A @ 90 V AC to 264 V AC - Input Current
24A @ 3.3V DC - Output Current
24A @ 5V DC - Output Current
18A @ 12V DC - V1Output Current
18A @ 12V DC - V2Output Current
18A @ 12V DC - V3Output Current
0.8A @ -12V DC - Output Current
3A @ 5V DC - StandbyOutput Current

But even this is still not near the 28A that Aluvus said is recommended above? But this has got to be good enough, right?

 

[Matthias99]

18A @ 12V DC - V1Output Current
18A @ 12V DC - V2Output Current
18A @ 12V DC - V3Output Current
0.8A @ -12V DC - Output Current
3A @ 5V DC - StandbyOutput Current

But even this is still not near the 28A that Aluvus said is recommended above? But this has got to be good enough, right?

You didn't link it, but it looks like that PSU has three 12V rails, that can each supply 18A of current. That's a total of 54A (although you obviously can't actually pull that much, since that would be WAY more than 520W; there are probably other limitations that you didn't list).

You really don't need more than a good 350W or so PSU for the system you have described. You'll need something like 20A in total of +12V capacity (assuming ~100W for the E6600 and another 100W or so for the 8600, plus some slack). Something with more like 25-30A would give you more upgradability.

 

[rpf717rpf]

better?

Good, bad, overkill? I can probably get it for $80, which is only a bit more than the seasonic's 380watt

 

[Matthias99]

Originally posted by: rpf717rpf
Link

good, bad, overkill? I can probably get it for $80, which is only a bit more than the seasonic's 380watt

Wow, you totally hosed that link. I fixed it in my post.

According to SilentPCReview review link, these units are actually rebadged Seasonics (likely based on the S12 model), which are probably the best quiet/high-efficiency PSUs on the market right now. While even the 520W version is definitely overkill -- it should be a very quiet and high-quality PSU.

 

[Blain]

"The Truth About Graphics Power Requirements"

 

[myocardia]

Originally posted by: rpf717rpf
better?

Good, bad, overkill? I can probably get it for $80, which is only a bit more than the seasonic's 380watt

Overkill; get the 520 watt version of that same psu. It's more than enough for a single card system, and is as quiet.

 

[gramboh]

I just built a new PC with specs similar to yours and went with the Corsair HX 520. It was $129 (Canadian) and well worth it, the thing is very quiet and the modular connectors save you having a lot of extra cables in your case. So far I've noticed no ripple on any lines (only been using it a few days though). It's running an E6600 @ 3.4GHz, 2GB ram, 8800GTS 640MB (stock for now), 2 Seagate 7200.10's and a DVDRW as well as 3 case fans and the CPU fan (120MM's).

 

[Captante]

The Corsair 520 watt psu is manufactured by Seasonic & is one of the better 500 watt range models available ... its true that it does supply more juice then you'll need even if you were to go for an 8800GTS 640mb GPU but I always prefer to over-build my personal machines.


If price is a major concern there are however some excellant choices that will cost a bit les less & work just about as well: (Listed in order of overall quality)



SILVERSTONE ST50EF-Plus ATX 12V 2.2 500W @ $99 + $8 shipping


ENERMAX Noisetaker EG495P-VE SFMA ATX 12V Ver2.0 485W @ $85 + $6 shipping


FSP Group (Fortron Source) AX500-PN ATX2.2 500 Watt @ $69 + $7 shipping

 

[Teclis2323]

Yes, I fully understand your point. Apparently you didn't understand mine.