power supply question

Maj.Emish

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Dec 12, 2008
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k i'm running a 500w thermaltake psu, which powers a 250gig hdd, 1 sata dvdr, a radeon 3850 256meg card, 2 gigs of ram, and my am2 6000+. would i be safe getting maybe another gig of ram and a better vid card without needing to upgrade the psu?
 
I can't tell you that you're 100% safe without actually looking at the numbers, but I'm 99% sure you'll be just fine.
 
Don't go by what the video card box says though...They often overshoot the mark by as much as 150 watts.
 
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It depends on the card. Lower end cards will not need much power, high end cards need much more power. Also be sure that you have the correct connectors for your video card. Higher end cards require auxiliary power connections so make sure you have them, and enough of them, if the card you choose requires auxiliary power.
 
Toasteddude is right - a lot of it will depend on the video card you choose. The RAM isn't a big issue. The newer cards suck up a lot of power, as well as needing some special (or extra) connectors that your older PSU might not have. I think most enthusiast sites are suggesting at least a 600watt PSU when you start looking at things like a GTX 280 or higher or an AMD/ATI 4870 or higher. You could be ok, but sometimes the extra headroom is a good choice.

If you google "computer power supply calculator" you'll come up with several sites that offer software or lists to help you decide exactly how much power you'll need. Just remember to think about upgrading when you purchase. Your PSU is going to last a while, so get one that'll have room to grow :-)
 
An i7 w/6GB, 2 HDDs, 1 BD, 2 x 120MM fans and a HD4890 will only draw ~350W at load. A quality 450W like the VX450 from Corsair will be more than enough. Use an adapter for the second PCI-E power plug.
 
i did up my system with extreme power supply calculator (adding the components i want) at full load it recommended a 539 watt psu, if i went with just the vid card i'd have some headroom so i might just get the vid card, and it's a newer power supply so yeah it has the connectors for vid cards :D and thank you everyone for your input
 
List the exact boxes/fields you entered. Did you use this site? http://extreme.outervision.com/psucalculatorlite.jsp

Your current PC with a new video card will only draw 250/300W max.

Single Socket
High-End Desktop
i7 965
6 sticks DDR3
4870X2
2 SATA HDDs
1 BD
Fan Controller
3 x 120MM
90% Load

That's a high-end build. 510W according to that calculator. No idea how you managed 539W.
 
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Well, depending on what you want to upgrade to, you may need a new psu due to the need for an extra PCI-e connector.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817153088

If that's your PSU, you'll probably be fine assuming you don't go with a 4870x2 or GTX 295. At the same time, if you start putting in more components other than just a new video card, you may run into stability problems.

Use an adapter for the second PCI-E power plug.

I do not recommend using this. This should be a last resort as the smaller rails/connections are not designed to withstand the heavy loads of pci-e 6 pin connectors. I had a 480-watt thermaltake psu that I used while my 700-watt OCZ PSU was being RMA'd. It wasn't powering a terribly power consuming system either. For that, I used one of those adaptors. The system was very unstable on some games. If you only have 1 pci-e connector, I would recommend getting a new PSU w/ 2 pci-e plugs.

Does your PSU have 1 or 2 pci-e 6pin connectors?
 
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Uh...you do realise that a VX450 is more than sufficient for a 4870/4890 right? While using adapters on a sub-par PSU is a bad idea, the VX450 has 33amps on the 12v rails, which is plenty.

The VX450 is also conservatively rated, and can output close to 500W, but it only comes with one PCI-E power plug, not because it can't handle cards that require two six pins, or one six, one eight, but as a marketing decision so as to not eat into the HX520 sales.

Of course, if I had a GTX 285/295/HD4870X2, I would look higher than the VX450, but cards like the 4890 and 275 are not as power hungry as misinformed people are making them out to be, which is why they stupidly recommend 600W PSUs when a 450W or 520W will be perfectly adequate.
 
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hardhat - remember that those wattages are assuming 100% throughput. you really need to have some good headroom in a power supply, so i would never suggest anything less than say a 500watt PSU for an i7 system, and even that is really cutting it tight. just because your power needs don't actually "add up" to 500 watts doesn't mean you should go for a 400 or 450. PSU doesn't work at maximum capacity anyway, they are only really good to say 85% of their rating. so factor that in when you're doing the calculations.

besides - at the price a decent PSU it doesn't cost THAT much more to go from say a 400 to a 550 watt PSU. while i don't suggest going with a 1k overkill PSU, definitely give yourself some headroom and get something over 500watts.
 
General rule of thumb:

Budget PC: CX400 - VX450

Mid-End PC: HX520 - VX550

High-End PC: HX620 - TX650

Multi-GPU PC: TX750 - TX850

It's not difficult, a bit of common sense and research goes a long way.
 
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you should be fine, cpu's use up to 100 (thats about an i7). 500 should do
 
with my current build

amd am2 x2 6000+ windsor
2 ddr2 slots
1 dvd-r
1 sata hdd
2 cold cathodes
3 usb devices
1 80mm fan
2 120mm fans
1 hd 4870 (card i want to run)

running at 100% system load i got it to 380 the higher number was with more ram and the cpu utilization at 100%


YES I HAVE THE VIDEO CARD SOCKET ON MY PSU
 
Just to put power requirements into perspective I used some testing equipment from Siemens (my dad works there and yes that is the actual name of the company, Google it...) to test how much my computer was actually drawing from the wall; My data showed that my computer drew anywhere from 350 watts (idle) to 500 watts (load). So I'm guessing you will be fine with what you have for a while

My setup:

Power Supply: 1000watt Thermaltake

Processor: Intel i7 940 (@stock)

Graphics Card: BFG GTX 295 (@stock)

Memory: 3x, 2 gig OCZ Gold (@1.6Ghz)

Storage: 2x, 300 gig Western Digital Velociraptor (10,000 rpm)

2x, 500 gig Western Digital Caviar​
 
My Current System.

Antec NSK6580B Plane Black Computer Case with a added CORSAIR CMPSU-750TX 750W Power Supply (My two youngest kids got this at x-mass for me).
Mother board.
Intel? Mother Board DX58SO (the Wife picked it up at X-mass for me)
CPU.

Intel? Core? i7 processor 3.20 GHz and H/s/ fan (My oldest Son Picked this up for me a x-mass).

The rest of the stuff I picked up my self.


Memory.
8 gigs of Triple channel DDR3.
Video Card.
GeForce GTX 280 1GB GDDR3.
DVD Burner/Player.
Pioneer Black 4X Blu-ray DVD Burner SATA Model BDR-202BK
And a ASUS 20X DVD?R DVD Burner with LightScribe Black SATA
Hard Drive
Internal Seagate Barracuda ES.2 1TB 3.5" SATA 3.0Gb/s Hard Drive 1TB 7200 RPM 32MB Cache
Audio.
On Board 8-channel (7.1) Dolby Home Theater* audio subsystem with five analog audio outputs and two S/PDIF digital audio outputs (coaxial and optical).
My OS
XP Pro.
Monitor
24 inch GE

Its works for me.
 
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