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Smartpower 500w enough for x1900XT?
- Thread starter Shogo
- Start date
Ice Czar
Inscrutable
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- Jul 8, 2001
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http://hardforum.com/showpost.php?p=1028999636&postcount=25
http://users.erols.com/chare/elec.htm
http://www.xbitlabs.com/articles/video/display/gpu-consumption2006_4.html
watts \ volts = amps
(+12V1)
Athlon 64 X2 4400+ @ 110W \ 12V = 9.2A
(+12V2)
X1900 XTX @ 120.6W \ 12V = 10.9A
+2A per HDD, 0.5A per fan, 0.5 for PCI cards, 0.5 for the mobo
deduct one quarter of the rated amps to heat loss
place PSU on UPS or high quality new surge protector (MOV's wear)
no it would not be my first choice
you have a $650 card and a $465 processor + components
and your spending all of $63 dollars to keep it all from blowing up
Id recommend a supply with both tighter regulation, cleaner power and more headroom
will it work? most likely,
are they good supplies? they meet basic spec compliance
would I do it? no
Id guess your worse case runtime draw on the +12V2 rail to be about 13.5A
without overclocking and your derated +12V2 capacity about 14.25A
in a supply that is just of basic compliance,
your likely to see accelerated wear on the supply would be my guess
http://users.erols.com/chare/elec.htm
http://www.xbitlabs.com/articles/video/display/gpu-consumption2006_4.html
watts \ volts = amps
(+12V1)
Athlon 64 X2 4400+ @ 110W \ 12V = 9.2A
(+12V2)
X1900 XTX @ 120.6W \ 12V = 10.9A
+2A per HDD, 0.5A per fan, 0.5 for PCI cards, 0.5 for the mobo
deduct one quarter of the rated amps to heat loss
place PSU on UPS or high quality new surge protector (MOV's wear)
no it would not be my first choice
you have a $650 card and a $465 processor + components
and your spending all of $63 dollars to keep it all from blowing up
Id recommend a supply with both tighter regulation, cleaner power and more headroom
will it work? most likely,
are they good supplies? they meet basic spec compliance
would I do it? no
Id guess your worse case runtime draw on the +12V2 rail to be about 13.5A
without overclocking and your derated +12V2 capacity about 14.25A
in a supply that is just of basic compliance,
your likely to see accelerated wear on the supply would be my guess
Ice Czar
Inscrutable
- Joined
- Jul 8, 2001
- Messages
- 27,174
editing bump
Ice Czar
Inscrutable
- Joined
- Jul 8, 2001
- Messages
- 27,174
a good supply is the cheapest insurance policy you can buy 
topdragon147
Gawd
- Joined
- Jun 9, 2004
- Messages
- 928
would this be the same case for a 7800gtx?
Ice Czar
Inscrutable
- Joined
- Jul 8, 2001
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- 27,174
http://www.xbitlabs.com/articles/video/display/gpu-consumption2006_4.html
94.7W / 12V = 7.8A
drives and fans once they have spun up fall to a quarter of thier draw, they blip about a bit with seeks (moving the arm) but say 0.5A spinning HDDs, 0.2>0.3A fans depending on size and speed once spinning, generally you wouldnt be spinning up an Optical while everything else was pegged, but in that case add another 2A
the thing about the new CPU and GPUs is they are really hammering the power off and on, need more now, stop, now, stop NOW, each time that happens its a transient load and there can be an overshoot, in fact there always is, the question is how quickly it brings it back under control, thats called the transient response
Power Supply Testing Application Note (PDF)
SMPS = Switch Mode Power Supplies, what we are discussing
a supply that isnt loaded right next to its capacity will first run cooler and last longer, having a more robust thermal solution (heat kills(PDF), second it will very likely have better load regulation and transient response, meaning less overshoot, that is a pulse going through the circuits and is one of two key components of electromigration, "wearing" on circuits, and a higher quality supply will have far cleaner power, again pulses this time AC signals on the DC line.
power supplies arent easy to design, and component quality, more complex well regulated and cleaner filtering, and assembly with a high standard of quality control costs, but considering its the one component able to fry the rest or just slowly degrade them, its well worth the investment to get a good one.
unfortunately what sells PSUs is hyperbol, bells and whistles, fancy cables, lighted fans, windows, LED readouts, all of which have absolutely no bearing on the quality of the power, but cost.
(there are exceptions, Titanium plating looks spiffy and blocks EMI)
the PSU is a link in a chain
anywhere along the line from the utility to the VRM on the mobo you have 7 basic issues (PDF) that have to be handled
1. Transients
2. Interrupptions
3. Sag / Undervolting
4. Swell / Overvolting (overshoot, spike, surge)
5. Waveform distortion
6. Voltage Fluctuations
7. Frequency Fluctuations
if you respect the investment you have made in components you will get a high quality UPS, a high quality PSU and a mobo that is a proven overclocker
why the last?
because one of the primary reasons one board will overclock better than another aside from its BIOS options and the trace layout, is the stability of the onboard VRMs (Voltage Regulation Moduals)
This is an interesting thread.
94.7W / 12V = 7.8A
drives and fans once they have spun up fall to a quarter of thier draw, they blip about a bit with seeks (moving the arm) but say 0.5A spinning HDDs, 0.2>0.3A fans depending on size and speed once spinning, generally you wouldnt be spinning up an Optical while everything else was pegged, but in that case add another 2A
the thing about the new CPU and GPUs is they are really hammering the power off and on, need more now, stop, now, stop NOW, each time that happens its a transient load and there can be an overshoot, in fact there always is, the question is how quickly it brings it back under control, thats called the transient response
Power Supply Testing Application Note (PDF)
SMPS = Switch Mode Power Supplies, what we are discussing
a supply that isnt loaded right next to its capacity will first run cooler and last longer, having a more robust thermal solution (heat kills(PDF), second it will very likely have better load regulation and transient response, meaning less overshoot, that is a pulse going through the circuits and is one of two key components of electromigration, "wearing" on circuits, and a higher quality supply will have far cleaner power, again pulses this time AC signals on the DC line.
power supplies arent easy to design, and component quality, more complex well regulated and cleaner filtering, and assembly with a high standard of quality control costs, but considering its the one component able to fry the rest or just slowly degrade them, its well worth the investment to get a good one.
unfortunately what sells PSUs is hyperbol, bells and whistles, fancy cables, lighted fans, windows, LED readouts, all of which have absolutely no bearing on the quality of the power, but cost.
(there are exceptions, Titanium plating looks spiffy and blocks EMI)
the PSU is a link in a chain
anywhere along the line from the utility to the VRM on the mobo you have 7 basic issues (PDF) that have to be handled
1. Transients
2. Interrupptions
3. Sag / Undervolting
4. Swell / Overvolting (overshoot, spike, surge)
5. Waveform distortion
6. Voltage Fluctuations
7. Frequency Fluctuations
if you respect the investment you have made in components you will get a high quality UPS, a high quality PSU and a mobo that is a proven overclocker
why the last?
because one of the primary reasons one board will overclock better than another aside from its BIOS options and the trace layout, is the stability of the onboard VRMs (Voltage Regulation Moduals)
This is an interesting thread.
p0intblank
Limp Gawd
- Joined
- Jun 27, 2005
- Messages
- 371
Sorry to highjack, but I was about to post a thread asking something like this and I might as well do it here. Since the X1900XT recommends having 30 amps on the 12v rail would the OCZ ModStream 520 watt psu with 26 amps on the 12v rail be good enough?