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Best power supply for Core i7?

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August 22, 2009 10:29:35 PM

Hello, here is my system. It's about a three weeks old now and I couldn't be happier with my setup.
For the actual issue, go below the specs

Core i7 920 (Clock speed stock, memory overclocked to 1600, stock cooler) D0 Stepping (Whats that?)
Gigabyte GA- EX58 UD4P
OCZ Gold 1600 6gb Triple Channel
Diamond HD 4890 (Plan to add two more later)
Antec Nine Hundred
One SATA 7200RPM drive, one IDE DVD drive

My current issue is with my power supplies. I am using two 500 watt power supplies.

Power Supply #1: All of the fans, the DVD drive, the video card, and the motherboard power.

Power Supply #2: The 200mm fan, and the CPU power.

This seems to be holding up very good, although the current configuration is not exactly rock solid stable. It's frozen up a few times, but not enough to bother me. (Just about once per two weeks)

The only major setback is the temperatures I'm getting. This is almost unreal!
The two main sources of heat are the video card (which is expected) and power supply #1 which seems to be at it's peak.

What power supply would be best for my system? Remember it has to power at least one more 4890 with a lot of power left over.

Thanks

More about : power supply core

a c 248 ) Power supply
August 22, 2009 11:29:18 PM

Hmmmm.....three ATI Radeon HD 4890 graphics cards operating in triple Crossfire mode. I know your Gigabyte mother supports three way Crossfire but I don't have any reference material that shows power consumption for such a configuration. Most of the reviews are about gaming benchmarks for an overclocked cpu and two 4890 cards operating in dual Crossfire mode. All of the reviews used a 1000 watt power supply for the dual Crossfire tests
August 23, 2009 2:24:40 AM

In MicroCenter (Our somewhat local PC store) they said one 4890 alone can take up to 380 watts by itself. Wow..
Related resources
August 23, 2009 4:07:56 AM

That's complete bull, honestly.

As for the PSU I'd recommend? How about the Corsair 850TX?
a b ) Power supply
August 23, 2009 4:56:37 AM

cjl said:
As for the PSU I'd recommend? How about the Corsair 850TX?

Only has 4 PCIe connectors. HX850 has 6.
August 23, 2009 5:19:31 AM

3 4890s and an i7 will have plenty of margin on the Corsair 850 (either of the two, HX or TX). My quadfire 4870x2 rig with an i7 only pulls around 800W peak, so 4890 trifire should be below that.
a b ) Power supply
August 23, 2009 5:44:43 AM

Try switching mobo power to PSU #2. And make sure that both psu's maintain strong (ground) contact with the each other and the case. Like a good gauge wire from a screw on the psu that's outside the case to a screw on the case. Otherwise they may have different "grounds" and that could cause some voltage issues for you. And potentially, some heat.

As for a replacement PSU, I'll let the others speak.
August 23, 2009 5:46:19 AM

xc0mmiex said:
i wouldn't go for anything lower then 950W just to be on the safe side... but thats me, i wouldn't risk 3 X 4890's and an i7

http://www.newegg.com/Product/Product.aspx?Item=N82E168...


With rebate, this is only $20 more than others I was looking at.

And I looked into power usage for 4890, the highest I've seen is 320. Not 380. And most of the bench's are even lower than 320.
August 23, 2009 6:22:51 AM

Keep in mind that most reviews measure total system power consumption, which will make things look FAR more power hungry than they really are.
August 23, 2009 3:25:23 PM

todd5854 said:
.

What power supply would be best for my system? Remember it has to power at least one more 4890 with a lot of power left over.

Thanks


Antec True Power Quattro 1000 watt or a Corsair with the same wattage. The first is one of the best also if not so much known as the other. 64amp on 12V it's really good and it has 8 PCI-E links, both 8 and 6 pin.
a b ) Power supply
August 23, 2009 3:38:48 PM

selea said:
Antec True Power Quattro 1000 watt or a Corsair with the same wattage. The first is one of the best also if not so much known as the other. 64amp on 12V it's really good and it has 8 PCI-E links, both 8 and 6 pin.

The TPQ 1000 has 70A on 12V and only 4 PCIe connectors, which are both low for a 1kW PSU.
August 23, 2009 5:23:03 PM

theAnimal said:
The TPQ 1000 has 70A on 12V and only 4 PCIe connectors, which are both low for a 1kW PSU.


Yes, you are right my mistake. I didn't recheck the specifics and since I have a TPQ 850 modded with 8 PCI-E lanes I supposed it was the same everywhere.

However I don't get what you intend for "low". 70A is fine for a 1KW PSU also because he doesn't need all that power anyway. I don't think three 4890 requires more than 60A in the rails.
August 23, 2009 5:24:55 PM

Quote:
He doesn't need a 1000W PSu


I know, but since the cost difference between an 850W and a 1000W PSU is not so great and he use a CrossFireX setup I wanted to be more on the future proof side. I've said Corsair was a very good choice.
August 23, 2009 9:29:34 PM

anyone read what i linked? 850 corsair is fine, and if he wants tri-fire, use the 850HX for the extra adapters
a b ) Power supply
August 23, 2009 9:48:32 PM

trifire 4890 tdp is is 698 watts
a b ) Power supply
August 23, 2009 10:41:07 PM

obsidian86 said:
trifire 4890 tdp is is 698 watts

TDP does not equal power consumption.
a b ) Power supply
August 23, 2009 10:45:17 PM

ok 698 watts at 100% load
a b ) Power supply
August 23, 2009 10:50:49 PM

obsidian86 said:
ok 698 watts at 100% load

According to xbitlabs the 4890 only uses 120W running 3DMark06. It won't use close to 200W even running Furmark.
August 23, 2009 11:33:31 PM

obsidian86 said:
ok 698 watts at 100% load


I'll give you maybe 698 watts total system power at 100% load.
August 24, 2009 3:20:29 AM

I want something powerful enough to handle the system as if EVERYTHING is on 100% load. I plan on overclocking as high as my system will let me, without doing damage to components. All three 4890's may see some overclocking as well.
a b ) Power supply
August 24, 2009 3:32:37 AM

todd5854 said:
I want something powerful enough to handle the system as if EVERYTHING is on 100% load. I plan on overclocking as high as my system will let me, without doing damage to components. All three 4890's may see some overclocking as well.

Anandtech measured an i7 @3.2 w/3 HD4870 running 3DMark Vantage @ 574W from the wall. After adding 100W for additional stress on the CPU/RAM/mobo and factoring in 80% efficiency, the system would max out at 540W DC.
a c 248 ) Power supply
August 24, 2009 4:06:35 AM

the animal - Thanks for posting the HD 4870 triple Crossfire power consumption from the Anandtech article. None of the usual power consumption charts are up to date.
August 24, 2009 4:27:57 PM

theAnimal said:
Anandtech measured an i7 @3.2 w/3 HD4870 running 3DMark Vantage @ 574W from the wall. After adding 100W for additional stress on the CPU/RAM/mobo and factoring in 80% efficiency, the system would max out at 540W DC.


Wow, really? Only 540? Maybe all I need is a good 700 then...I really like headroom, but if it's overkill then I'll pass. Anything from 700 watts to 1000 watts appears to be in just about the same price range.
a c 248 ) Power supply
August 24, 2009 5:27:58 PM

When I mentioned a 1000 watt power supply during testing in my original post. I didn't mean to imply that a 1000 watt psu was necessary. I was just reporting what was used during testing. Sorry if there was a misunderstanding.
August 24, 2009 5:36:49 PM

well, i picked up a corsair HX1000w for relatively cheap, if you aren ot in a hurry, watch and see what you can pick off

now granted, I found out later that the HX1000w is based on a somewhat aging design (they squished two 500w PSU to make a 1000w psu) when the newer stuff is a true 1 PSU design. Although at the launch of this 2 PSU combo, it was as good as you can get design for true high wattage, when simpler designs of single PSU like were either not delivering enough juice, or not stable enough. Now its changed tho, with the newer stuff back to single PSU design.
a b ) Power supply
August 24, 2009 6:13:25 PM

I'm getting different numbers for 3 4890s in crossfire.
http://mark.zoomcities.com/images/gfx/GFXpowerchartbybr...

This site shows 421w for them at load, and that's not overclocked.

This article, which is the best i've seen at breaking down the actual power use of a system.
http://www.xbitlabs.com/articles/coolers/display/system...

Puts an i7 system not overclocked, a GTX295 (which uses about 100w less then the 3x4890s), single hard drive, 3x1 GB of RAM at would be about 600w of power used at load with the 3-4890s. That is with nothing overclocked. The OP obviously has a highend system, his i7 (DO) will probably be clocked to 4.0 or higher, his 4890s will also be overclocked, i doubt if he is going to only use a single HD for any length of time. Once he's tweaked his system i bet his at load power consumption will be well over 700w. If i had just dropped over $2,000 into a top end gaming system, spending another $100 for a 1,000w + quality power supply is what i'd do.

http://www.newegg.com/Product/Product.aspx?Item=N82E168...
http://www.jonnyguru.com/modules.php?name=NDReviews&op=...

yeah, overkill and i'll admit it, but the price is $100 more then the Corsair 850HX and with so much invested in a top end system, i'd spend it.
a c 248 ) Power supply
August 24, 2009 6:21:00 PM

dirtmountain - The differences in test results are par for the course. It's quite normal because there is no standard testing procedure or reporting criteria. I'll report power consumption from one review. Others will report power consumption from other reviews. Sometimes the numbers are for total system power draw at an electrical wall outlet. Sometimes they are not. Quite often different software and utilities are run during testing. It's all mixed up.
a b ) Power supply
August 24, 2009 6:38:11 PM

Yeah, that's why i like that xbitlabs link. The guy that ran it made some special apparatus to measure everything in a system. In the comments area of the article he also says at some time in the future he'll write another article to cover overclocking. I sure agree with you that it's tough to get accurate power use readings.
August 24, 2009 7:15:26 PM

theholylancer said:
well, i picked up a corsair HX1000w for relatively cheap, if you aren ot in a hurry, watch and see what you can pick off

now granted, I found out later that the HX1000w is based on a somewhat aging design (they squished two 500w PSU to make a 1000w psu) when the newer stuff is a true 1 PSU design. Although at the launch of this 2 PSU combo, it was as good as you can get design for true high wattage, when simpler designs of single PSU like were either not delivering enough juice, or not stable enough. Now its changed tho, with the newer stuff back to single PSU design.


The HX1000 is still one of the best you can get - each of the "500W" PSUs that is in it is capable of 750+, so you could probably hit 1500W on the Corsair without problems. It's just overkill for most systems.
a c 248 ) Power supply
August 24, 2009 7:37:11 PM

dirtmountain said:
Yeah, that's why i like that xbitlabs link. The guy that ran it made some special apparatus to measure everything in a system. In the comments area of the article he also says at some time in the future he'll write another article to cover overclocking. I sure agree with you that it's tough to get accurate power use readings.


theanimal likes xbitlabs too. I've had the site bookmarked for quite some time but haven't really looked at it in depth. I guess it's time to go see what the site has.
August 25, 2009 9:25:24 PM

I talked to the great people at MicroCenter (Not being sarcastic) and they pointed me to an Antec Quattro 1000. Honestly after talking to everyone, I think even the 850 is a lot. It's priced right.

Currently the system is being powered by two 500 watt's. If the whole system doesn't use 500 watts, couldn't I just use one 500 watt power supply?
August 25, 2009 10:23:43 PM

For right now, you could definitely use a single, good quality PSU. If you really plan to trifire later though, you'll want a bit more than that.
August 26, 2009 5:48:35 AM

My main 500 watt (that's powering the motherboard and video card) is from a reputable company. Cooler Master. I only had to change the fan, the included one made an unbearable rattling sound. Switched it with a TriCool, everything's fine.

Unless I don't need it, I'm really leaning towards the Antec Quattro. 850 or 1000. Whichever the system needs at that time. My friend bought the 850, which currently for his system is overkill. (Core i7, with 1 HDD, one DVD, one 8800gts) But he too plans to get a 4890.

Any opinions on the Antec Quattro's?
May 10, 2010 7:41:24 PM

i watched an intel build of a gaming rig very similar, and they suggested the Corsair 1000w no less.
!