Help - GPU Upgrade Do I Need New Power Supply?

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nuyork

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Hi,

I am going to be upgrading my PC soon and need some advice on what new power supply to get as I'll be upgrading my graphics card and not sure how much power it needs and my total system usage.

System Specs currently:-

Pentium D 930 3.0GHz
768MB DDR2-533 RAM
ATI Radeon 9550
1 SATA HDD
1 IDE HDD
1 DVD Writer
1 DVD ROM
Sound Blaster Live PCI card

At the moment I have an AOpen 400W PSU.

Using the eXtreme Power Supply Calculator it states that I'm using around 275W of power. If change the video card from 9550 to X1950 Pro the total goes up to 323W. So looks like the X1950 Pro uses up about 48W of power (I've heard high on other sites).

Now I want to upgrade the graphics card to a ATI Radeon X1950 Pro AGP. I've been doing alot of research and found alot of people warning to make sure that your PSU can handle 30A on the 12V rail to run the X1950 Pro card. This is also recommended by a manufacturer to have 30A on the 12V rail. And another website states that "Just make sure you have a 450w power supply or better (18a on the 12v rail at the minimum.)". So I'm not sure which one to believe - 18A or 30A?

Looking at the specs of my current PSU (see link), it looks like it doesn't support even close to 18A or even 30A. So I guess I need a new PSU right?

Can anyone recommend a PSU that will support my new video card?

The closest and cheapest match I've found is the CoolerMaster Extreme Power 650W PSU. This PSU has 18A on each 12V rail, but will that be good enough since one of the manufacturers and a few people mentioning (here and here) that it is recommended for 30A on the 12V rail. I'm not even sure if 650W PSU is overkill for the system in general, since at the moment it's only using 275W. And I'd rather have a PSU between 450W and 550W, but cannot find one that supports 18A on the 12V rail as a MINIMUM.

I wouldn't want to get this new graphics card and it doesn't even work in my system at all.

Please any help guy on this matter? This whole AMPS on the RAILS thing is completely new to me, and luckily I've done a bit of research before I went ahead and bought it.

Thanks!
 
I would recommend an Antec power supplies, but Zalman PSU's are quite nice because they heavily favour power on the 12v Rails.

Here is the specs for an Antec earthwats (antec's entry level model) 430W.
http://www.antec.com/us/productDetails.php?ProdID=27430
spec sheet here
http://www.antec.com/specs/EA430_spe.html
notice that it has 2 12v rails, one with 17A and one with 16A. That gives you 33A in total on both rails. The rails can be combined when you calculate your total.

If you like something a bit more powerful, this one has 44A spread over its 3 rails.
http://www.antec.com/us/productDetails.php?ProdID=23550
spec sheet
http://www.antec.com/specs/TP3_550_spe.html
 
I've heard bad things about the Extreme Power series of PSUs from CM and wouldn't recommend them.

Sapphiron said:
notice that it has 2 12v rails, one with 17A and one with 16A. That gives you 33A in total on both rails. The rails can be combined when you calculate your total.
Click to expand...

That type of calculation is wrong. One should use the maximum wattage supplied over the 12V rails and divide by 12V to calculate the combined amperage over the rails. That's why they say "* Total: +12V output: 30A" and not 33A. This value can sometimes differ quite a lot.

The Antec Earthwatts 430W Sapphiron mentioned would be way better than the Aopen and sufficient enough for the OP's needs IMO. I wouldn't use that AOpen on such a system. The earhwatts is also very efficient (up to 85%) which is very good. It's a decent power supply...I almost bought it myself but I rather went with an iGreen 600W because I don't ever want to upgrade my PSU if I want to use SLi or anything else. I'd get the earthwatts if I were you. :)
 
Keep in mind that a PSU's efficiency lessens with age, so you should compensate a little bit for expansion and age.
 
Also, that PSU calculator you used is for an instance when everything in your system is consuming the maximum amount of power that they can...which will probably never be the case, so your system will generally use less than indicated by it.
 
killadoob said:
U Sure You Wanna Spend That Cash On Old Technology And Have To Upgrade In 4 Months Again?
Click to expand...

Yea, PCI-e FTW!
only downside it that you getting a AGP card :o IMO I would have just saved up and got a new system :p I am still sitting with a Sempron 2600+ & a 6600! :eek:
 
Praeses said:
That type of calculation is wrong. One should use the maximum wattage supplied over the 12V rails and divide by 12V to calculate the combined amperage over the rails. That's why they say "* Total: +12V output: 30A" and not 33A. This value can sometimes differ quite a lot.
Click to expand...

Ok, true, but on high quality PSU's, its the easy way of calculating it :p
 
true AGP is not good to invest in.

Get a ASUS P5k motherboard and a 7600GT graphics. The 2 together should cost you no more than R2200. then you have got a motherboard that will take anything up to an intel Core2 Quad and basically any graphics coming out in the next 18 months
 
PCI-E 2.0 cards will be backwards compatible with PCI-E 1.0 slots (like AGP 4x and AGP 8x)
 
Thanks for all the replies guy. A really big help. I'll look at what is available and at a good price and decide them. I didn't realise that it was the amps of the combine 12V rails.

Well I was thinking long and hard about this whole upgrading story, and I have about 40K with which I can spend on a new system, but been looking around and there's nothing that I really want at the moment that stands out. Would rather wait for newer generation hardware and see what happens. So decided to just spend about R3K and do a small upgrade.

I'll probably get a whole new system next year sometime. But mainly this upgrade is just to tide me over for HL2 Episode 2 and a few other games. I have my Wii and 360 to keep me company in the meantime.

:L:
 
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