Psu good enough?

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joodz
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I just bought a HIS radeon 6950 2gb video and a new kingwin 750w psu, BUT the kingwin is causing my computer to freeze during gaming and other random times. I'm sure its the psu cause i put the old one back in and everything is back to normal. The psu that works is a Raidmax 530w, its about 2 years old. Will that be able to handle my 6950? If only for a few days unil my new psu (going with corsair now!) comes in the mail.

Thanks in advance for any advice.

Tivon
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I did some reading to find that the Power Consumption of the 6950 is 188watts idle ~ 331watts max. Then you have to add in other parts of the system that might push you to the borderline. When I upgraded to a 6850 I was shocked that it runs 100watts less than my older 4870. So I guess your Raidmax 530 is just over the 500 - 550watts minimum requirement. If that new PSU fails then I would return it and get the Corsair for sure. :)

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GraysonPeddie
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Hey Tivon. Is the idle and max power consumption for the entire system? I found it hard to believe that the 6950 alone will push up to 100+ watts at idle.

Anyway, I don't think I'd trust PSUs having 4 +12v rails.

I mean, for 4 rails, you can have up to 624 watts (52 amps) total. But for Cougar 700w, this power supply has two +12v rails with 30 amps each and can push up to 648 watts. This should help with the freezes that you're having problems with Kingwin power supply.

Pardon me for bringing up a topic about rails, but I thought I can help out with the problems you're having with the Kingwin 750w PSU.

Since you're going with Corsair, could you tell us what model of PSU you're getting?

HTPC: AMD Athlon X2 4050e CPU with 780G ATX motherboard running Windows 8 DP (4GB) and Ubuntu; Server: AMD AII X2 240e CPU with 880G-based ATX motherboard running Ubuntu Server 10.04 LTS (8GB)

2 pairs of Insignia NS-B2111s (front/rear), Pioneer SP-C21 Center Speaker, and 12" Velodyne Sub

Just ordered HP Pavilion dv7-6165us from QVC. Will have it by next Friday.

joodz
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I decided on the 750AX from corsair. Its gold certified and on the amd website it says its certified for 2 6950s. As for the kingwin, its already boxed up and ready to get shipped back for a refund.

hnkftalnot
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I think GraysonPeddie is right about those numbers being total system power, since a graphics card with two 6-pin PCIe power connectors can only draw 225Watts max anyway.

GraysonPeddie
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That's a very high quality power supply. I hope you'll enjoy it! :)

HTPC: AMD Athlon X2 4050e CPU with 780G ATX motherboard running Windows 8 DP (4GB) and Ubuntu; Server: AMD AII X2 240e CPU with 880G-based ATX motherboard running Ubuntu Server 10.04 LTS (8GB)

2 pairs of Insignia NS-B2111s (front/rear), Pioneer SP-C21 Center Speaker, and 12" Velodyne Sub

Just ordered HP Pavilion dv7-6165us from QVC. Will have it by next Friday.

Tivon
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I tend over estimate on power for the good of the system. Because we don't know what the other parts are in his system I will guess mid-range or better. It is best to keep the whole system running under 80% of the total power for longer life and clean power. If a 530 Rainmax does the job then that's fine.. but as stated on the video card box they recommends a minimum of 500 watts. And to prove my point, if 225watts is the Max on the card then why do these benchmarks (listed below) have higher numbers? Idle power is one thing, but when playing games and multitasking it is a whole other arena to consider. However on the flip-side I agree my numbers are calculating high, but like I said before, factoring in unknown system parts + video card = probably best to get something good for present and future upgrades. And besides now we don't have to deal with his PSU problem anymore. ;)

http://www.bit-tech.net/hardware/2010/12/16/ati-radeon-hd-6950-review/10

http://www.tomshardware.com/reviews/radeon-hd-6970-radeon-hd-6950-cayman,2818-21.html

My system dropped 100watts upgrading from a 4870 to a 6850! :)

GraysonPeddie
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Cool. It'd be nice for newer GPUs to be more power efficient year-by-year. :)

HTPC: AMD Athlon X2 4050e CPU with 780G ATX motherboard running Windows 8 DP (4GB) and Ubuntu; Server: AMD AII X2 240e CPU with 880G-based ATX motherboard running Ubuntu Server 10.04 LTS (8GB)

2 pairs of Insignia NS-B2111s (front/rear), Pioneer SP-C21 Center Speaker, and 12" Velodyne Sub

Just ordered HP Pavilion dv7-6165us from QVC. Will have it by next Friday.

hnkftalnot
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Tivon wrote:It is best to keep the whole system running under 80% of the total power for longer life and clean power. If a 530 Rainmax does the job then that's fine.. but as stated on the video card box they recommends a minimum of 500 watts. And to prove my point, if 225watts is the Max on the card then why do these benchmarks (listed below) have higher numbers?

Those numbers in the reviews you linked are still total system power draw. In the bit-tech review it says "Watts at socket" at the bottom of the graphs, and in Tom's review there's also a mention of "system power".

I got to 225W because a 6950 has two 6-pin power connectors, the PCIe power specifications are like this:
The slot itself can deliver up to 75W (for all PCIe versions; 1, 2 and even 3)
a 6-pin can deliver up to 75W
an 8-pin can deliver up to 150W.

Also the GPU box mentions the total system power as well, since the wattage of the actual video card isn't relevant to most people and they can't have people complaining that their 300Watts PSU can't handle it or doesn't even have PCIe connectors. This is kinda confusing and a lot of people buy a PSU way over their heads because of this, and cheap brands make use of that by overspeccing their PSUs: the buyer of a cheap 800Watts PSU is unlikely to find out it can't do over 600 Watts since his system wouldn't ever need it anyway.

I agree with the 80% one should calculate off the draw the PSU can handle, for the reasons you mention. And another 50-100W overhead wouldn't hurt for future upgrades. Besides, due to large demand on heavier PSUs, being from unknowing customers or not, even quality brand PSUs have a good price ;).

Tivon
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Another good thing about buying a nice large power supply, other than a stable system, is that they only draw the power required by the parts. So for anyone else that is not a geek, that means a 750watt psu is not going to pull 750watts 24/7, but rather the amount your system parts are hungry for.

I'm probably wrong like you said hnkftalnot. So if we have a card that has two 8-pins then it does 375watts. If we take 75+75+75 we get 225watts. Funny how that works out because the extra 2 wires from 6 to 8 are only ground wires.

hnkftalnot
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I thought the extra 2 wires on an 8-pin are one +12volt and one ground. Still I also find it weird how one +12volts wire can deliver the extra 75 watts on its own.. but these are just the PCIe specs I'm posting and I'm unsure how it works out exactly.

Cards with two 8-pins are kinda rare as you know, I think the manufacturer has some overclocking in mind when adding those, since 375W is really a lot.

And yeah a PSU will only draw the power required for the system, so it's still the safest bet to go with a larger PSU even if you don't need it and it wouldn't hurt your power bill - Better be safe than sorry :). Although to reduce costs on the purchase I think one should really look at 80% of the actual max requirements of the system, any future upgrades aside. But a bit extra doesn't hurt like you say.