Why do i need an 850w PSU to power SLI/CF

[Pandamonia]

Why don't you go for it? If it works then good. If it blows up then good for you.

Im wondering if i can get away with it for a while.. hmm

 

[Slomo4shO]

For Corsair RM1000:
Continuous power: 1000w
Peak power: 1100w

The RM1000 has poor build quality, there are much better options at the around same price point. The Cooler Master V1000, XFX ProSeries, or EVGA SuperNova P2 are great alternatives.

 

[Attic]

Some of us don't hold PSU manufactures to the letter of the law on these things, we just hold em to what works and who delivers the best results. Corsair is great, Seasonic is great, few other units.

Bottom line, you won't find anyone here endorse the idea of running 290 xfire on a 620W rated unit. Leave some headroom above peak usage for the PSU when designing a system.

 

[Pandamonia]

The RM1000 has poor build quality, there are much better options at the around same price point. The Cooler Master V1000, XFX ProSeries, or EVGA SuperNova P2 are great alternatives.

Corsair is the only PSU that hasnt blown up on me for no reason.

XFX, OCZ, Coolermaster have all gone up in a puff of smoke.

 

[Slomo4shO]

Corsair is great

Corsair is the only PSU that hasnt blown up on me for no reason.

I am still not sure why Corsair continues receives so much reverence from the online community. Their newer models are no longer manufactured by Sea Sonic and most of their lineup is from CWT. Only the AXi series is by Flextronics (including AX1200) and the AX series is by Sea Sonic (including HX650).

XFX, OCZ, Coolermaster have all gone up in a puff of smoke.

OCZ is crap and so is most of Cooler Masters lineup beyond the Sea Sonic built V series. XFX Pro > XFX Core as far as quality is concerned.

 

[Pandamonia]

I am still not sure why Corsair continues receives so much reverence from the online community. Their newer models are no longer manufactured by Sea Sonic and most of their lineup is from CWT. Only the AXi series is by Flextronics (including AX1200) and the AX series is by Sea Sonic (including HX650).


OCZ is crap and so is most of Cooler Masters lineup beyond the Sea Sonic built V series. XFX Pro > XFX Core as far as quality is concerned.

Why is the AX and AXi made by different companies? its the same PSU is it not?

 

[cmdrdredd]

you see this makes no sense to me. i would say that running at 620w is exactly what its designed to do or its not a 620w PSU.

It sounds like sales talk to me.

Electronics degrade over time. The ability for the parts inside the PSU to pass through that current isn't a constant thing. A Good PSU will last a long time but I bet if you had the tools to measure the current it's able to handle on day one, and then use it for a period of two years and test that again you would see the numbers go down a bit.

 

[Slomo4shO]

Why is the AX and AXi made by different companies? its the same PSU is it not?

The AX series is the older models by Sea Sonic where as the AXi are the newer models by Flextronics which have voltage regulation performed by DSP and also includes a UBS link to customize fan profiles and monitor power input and output.

Here is a good review comparing the AX and AXi series:

http://www.xbitlabs.com/articles/cases/display/corsair-ax-axi.html

 

[cmdrdredd]

I am still not sure why Corsair continues receives so much reverence from the online community. Their newer models are no longer manufactured by Sea Sonic and most of their lineup is from CWT. Only the AXi series is by Flextronics (including AX1200) and the AX series is by Sea Sonic (including HX650).


OCZ is crap and so is most of Cooler Masters lineup beyond the Sea Sonic built V series. XFX Pro > XFX Core as far as quality is concerned.

Remember the old Corsair HX750, HX850, and HX1000 line? The ones that got top tier marks in nearly every PSU review? Do you know who made them? It was Channel Well Tech(CWT). Not Seasonic. Did you do any research? Even Johnny Guru praised Corsair PSUs built by CWT. This was back in 2008. They were never built by Seasonic. They now may have some PSUs in the lineup built by Seasonic, but their best ones when they got into the PSU business were indeed Channel Well Tech.

So anyway, CWT is a VERY high quality OEM. Up there with Seasonic for sure. I still have a CWT built HX1000 from Corsair that has been running 24/7 365 on an overclocked system for 5 years now. It's gone through two system rebuilds and is as good as it was then.

 

[Attic]

I am still not sure why Corsair continues receives so much reverence from the online community. Their newer models are no longer manufactured by Sea Sonic and most of their lineup is from CWT. Only the AXi series is by Flextronics (including AX1200) and the AX series is by Sea Sonic (including HX650).


OCZ is crap and so is most of Cooler Masters lineup beyond the Sea Sonic built V series. XFX Pro > XFX Core as far as quality is concerned.

Yea, valid. The newer lines from Corsair are untried, but have some caveats.

I'm running the HX650, AX760, AX860, HX850, CM500, so mostly by Seasonic, but I have had no issues at all. The systems i've built for friends family all run Corsair and they've been rock solid for 4+years. I know something is working.

Well the HX850 (newest version) has a continous clicking noise that is common and it's gold rating is a bit lenient, only one I wouldn't buy again for the needs it was to meet but that's only because of the clicking.

Edit: Good info cmdrdreed.

 

[cmdrdredd]

Yea, valid. The newer lines from Corsair are untried, but have some caveats.

I'm running the HX650, AX760, AX860, HX850, CM500, so mostly by Seasonic, but I have had no issues at all. Well the HX850 (newest version) has a continous clicking noise that is common and it's gold rating is a bit lenient.

HX850 is Channel Well not Seasonic. Much of the line was CWT on the higher wattage units.

The AX series is Seasonic and from what I understand is almost an exact copy of the Seasonic X line repackaged with a Corsair name. Very high quality.

FWIW: Channel Well also builds PSUs for Antec and those get high marks as well.

Found this.

Corsair:

CX series
Cheap, budget-oriented units. Fixed cables, rated at 30-40C, mixed Japanese and Taiwanese caps, 80+, 2-3 year warranty. CWT made ones are overrated.

CX400 - SeaSonic S12II
CX430 - CWT DSA 380W
CX500 - CWT DSA 430W
CX600 - CWT DSA 500W

GS series
"Gamer series", fixed cables, blue LED fan, rated at 40C, mixed Japanese and Taiwanese caps, 80+, 3 year warranty.

GS600 - CWT PSHII
GS700 - CWT PSHII
GS800 - CWT PSHII

VX series
Mid-range enthusiast units, fixed cables, rated at 50C, Japanese caps, 80+, 5 year warranty.

VX450 - SeaSonic S12II
VX550 - CWT PSH

TX series
Mid-range enthusiast units, fixed cables, rated at 50C, Japanese caps, 80+ or 80+ bronze, 5 year warranty.

TX650 - SeaSonic S12
TX650-C - CWT PSHII
TX750 - CWT PSH
TX850 - CWT PSH
TX950 - CWT DSG

HX (original) series
Mid-range enthusiast units, modular cables, rated at 50C, Japanese caps, 80+, 5 year warranty.

HX450 - SeaSonic S12II
HX520 - SeaSonic S12
HX620 - SeaSonic S12
HX1000 - CWT PUC

HX (new) series
High-end enthusiast units, modular cables, rated at 50C, Japanese caps, 80+ bronze or silver, 7 year warranty.

HX650 - SeaSonic S12E
HX750 - CWT DSG
HX850 - CWT DSG

AX series
Extremely high-end enthusiast units, fully modular cables, rated at 50C, Japanese caps, 80+ gold, 7 year warranty

AX750 - SeaSonic X
AX850 - SeaSonic X
AX1200 - Flextronics, custom

 

[Slomo4shO]

Remember the old Corsair HX750, HX850, and HX1000 line? The ones that got top tier marks in nearly every PSU review? Do you know who made them? It was Channel Well Tech(CWT). Not Seasonic. Did you do any research? Even Johnny Guru praised Corsair PSUs built by CWT. This was back in 2008. They were never built by Seasonic. They now may have some PSUs in the lineup built by Seasonic, but their best ones when they got into the PSU business were indeed Channel Well Tech.

I also remember the older HX series by Sea Sonic from back in 2006. In fact, I own a 620HX and it is still going strong. So no, the reputation of the HX series was build upon Sea Sonic and not CWT. The recent models from CWT have been riddled with build quality issues.

 

[Pandamonia]

I also remember the older HX series by Sea Sonic from back in 2006. In fact, I own a 620HX and it is still going strong. So no, the reputation of the HX series was build upon Sea Sonic and not CWT. The recent models from CWT have been riddled with build quality issues.

i think thats what i have now HX620w

 

[ibex333]

don't mean to hijack the thread, but I got a question....

I am running 2x GTX 760's with a 600w OCZ PSU and playing Far Cry 3 with everything maxed out. On average fps is around 70 with spikes to 109 or so. But then I went to a few other areas with much foliage and such and got... around 40 fps.

WTF? Can this be because my PSU doesn't provide enough power, or is it something else? The setup I got should be able to run everything out there 70-100+ fps consistently no problem according to various reviews and benchmarks online.

 

[cmdrdredd]

I also remember the older HX series by Sea Sonic from back in 2006. In fact, I own a 620HX and it is still going strong. So no, the reputation of the HX series was build upon Sea Sonic and not CWT. The recent models from CWT have been riddled with build quality issues.

The models below the 750 never received the same praise.

i think thats what i have now HX620w

Maybe you should try your chosen setup and see what happens? You might be ok...if not you can always buy a new PSU later.

 

[cmdrdredd]

don't mean to hijack the thread, but I got a question....

I am running 2x GTX 760's with a 600w OCZ PSU and playing Far Cry 3 with everything maxed out. On average fps is around 70 with spikes to 109 or so. But then I went to a few other areas with much foliage and such and got... around 40 fps.

WTF? Can this be because my PSU doesn't provide enough power, or is it something else? The setup I got should be able to run everything out there 70-100+ fps consistently no problem according to various reviews and benchmarks online.

It's not the PSU and it's not your cards. The game is known to bog down and stutter a bit. Something about the engine.

 

[cmdrdredd]

mistake

 

[p0rkguy]

Because people don't know any better and will just tell you what the manufacturer recommends. These people don't know that this "recommend" takes into account for every hardware in your system and then some. It's also for manufacturers to protect themselves in case of any issues. One less idiot for them to deal with.

 

[Morbus]

Long ago, I had a then 3 years old no-brand 550W PSU. I then installed a HD4890 1GB, which eats up 190W at full usage. It was a messy job, because the PSU didn't have PCIe connectors and it only had one rail for everything where the VGA asked for two... Anyway, with a very messy wiring solution, and an open case with a noise external fan pointing at the computer, I ran the VGA with that old PSU. But I had to underclock it from 975MHZ down to 950MHZ, because otherwise it would become unstable and crash the system.

My computer was basically a zombie. But it worked and it worked like that for almost a year, before the by then 4 year old PSU crapped out for good.

To this day I am amazed that, not only did I manage to run the system like that in the first place, complete with a crappy white OEM tower and all, but it also lasted almost a year and, when the PSU died, it didn't take anything with it.

All this without any backup solution in place, so, living on the edge for the cash-strapped enthusiast!!!

Ah, those were the days...

Anyway, DO NOT base a powerful system on a crappy PSU. Those things die more often than any other part on your system, believe me. And that's even with a nice UPS to protect it!

 

[Pandamonia]

normally this wouldnt be an issue but i just spent £440 on a 1440p asus, £900 on new CPU, mobo and ram.

Still have £900 to spend to get my SLI/CF and PSU

 

[Slomo4shO]

The models below the 750 never received the same praise.

That is a matter of opinion. Seems you have forgotten the response received by the original HX series when Corsair was just entering the PSU market... Either way, I am not here to debate your jaded opinion so I will end that discussion here and get back to the topic at hand.


OP, The EVGA SuperNOVA 1300 G2 is currently £151.80 at Dobs and appears to be the best value at the £140-160 price range.

2x MSI R9 290 GAMING TWIN FROZR IV for £358.80 each will set you below budget with above PSU.

 

[blastingcap]

OP everybody here has given you reasons and shown you the evidence. If you want to be penny wise and pound foolish go ahead and buy a PSU that's barely adequate, but don't cry if you have issues down the road. Also, I'm not sure if people have said this yet but the max wattage of a PSU is not the rated wattage. First of all, a PSU's rated wattage should be the highest wattage it can maintain continuously indefinitely, but many shady manufacturers don't meet that spec and treat the rating as a "peak" load that can't be sustained indefinitely. Second of all, you need to look at the amperage rating on the 12V rail(s). Your CPU/GPU/mobo draw from the 12V rail so only 12V rail wattage counts for their purposes. For instance a 1000W PSU that only has 10 amps available on the 12V rail means only 10 x 12 = 120 watts are available to power your CPU/GPU/mobo. Chances are the 620W PSU you are looking at has substantially less than 620W available on the 12V rail(s).

I also think this topic belongs in Power Supplies. http://forums.anandtech.com/forumdisplay.php?f=48

 

[stahlhart]

Moving discussion to Power Supplies.
-- stahlhart

 

[coffeejunkee]

HX620 is very good and I think it can actually handle it if you refrain from overclocking the gpu's. It has only 2 pci-e connectors though so you will need adapters.

I'd get at least 750W when buying a new psu though.

 

[TemjinGold]

OP: Don't OC and that PSU should work fine actually. You will notice one definite disadvantage to run at capacity and that's noise. I overbuy my PSU not because I honestly think I need it but because running with a lot of headroom keeps the PSU fan off. If noise doesn't bother you, you don't live in a hot climate, and you are fine with not OCing for now, it really should work as long as there's nothing wrong with your unit.