Power requirements for 5770

[drakore]

I checked on google, all I could find is they recommend a minimum of 450W. Does anyone know the current required on the 12V rails?

I really want to used this with a 300W TFX PSU and it only has 21A on the 12V rails. I would be pairing it with a Q9550S (65W TDP).

Thanks

[W1zzard]

check my review, take the furmark max power and divide it by 12V to get amps needed

[drakore]

Cool thanks, but where is your review located?

[W1zzard]

http://www.techpowerup.com/reviews/HIS/HD_5770/

[Mats]

I'd say you'll be fine. Since you need a TFX I guess you won't have a lot of drives connected to it.
If it's possible to run a Q6600 and a first gen 8800 GTS on a cheap 300 W HEC then I wouldn't worry (http://www.silentpcreview.com/forums/viewtopic.php?t=3075&postdays=0&postorder=asc&start=212).

Or, wait for the Xbitlabs review. They usually test the power consumption individually, here are the results for the 5870 (http://xbitlabs.com/articles/video/display/radeon-hd5870_7.html#sect0).

You don't need a Q9550S, it's not worth the extra money, which currently is $130 more (http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=q9550&x=0&y=0) at newegg!!

Q9550S $350
Q9550 $220
i7 750 $200

Check this review (http://www.silentpcreview.com/article954-page4.html). The difference in power draw is small, and when both are undervolted (next page), there's NO difference!!

Since you're not telling us about the rest of the specs it's not that easy to recommend, but an i7 750 would be cheaper, faster and cooler running than a Q9550.
Maybe you already got mobo and RAM, but if you don't then I don't see the reason for going S775.

[drakore]

Cool thanks. Based on those figures a 5850 would draw 12.5A on the 12V rail. If i take 80% efficiency from the 21A on the 12V rails I will have about 16.8A usable current. Leaving me about 4.3A for the rest of the system. Is that enough do you think for 4GB DDR2-800 @ 2.1V, Q9550s at stock voltage, a couple of case fans, and a 250GB SSD?

I am paying about $210 for the Q9550S, I can get the Q9550 for about $180, but I am getting a deal on other items if I buy the Q9550s. I already have parts for S775, otherwise i would go with the i5.

[W1zzard]

looks like finding the data in my review was too hard. i see 9.3A worst case for the 5770. psu 12v rails listings are after inefficiency, not before

[Mats]

Is that TFX 21 A single rail? You keep saying rails, but now you say it's single. Ouch.

Get a dual 12 V instead, maybe this one (http://www.seasonicusa.com/tfx.htm). Make sure the size is the same. Edit: Which happen to be 21 A combined, I dunno.

You changed to a 5850?:shrug: Title says 5770.

[drakore]

Is that TFX 21 A single rail? You keep saying rails, but now you say it's single. Ouch.

Get a dual 12 V instead, maybe this one (http://www.seasonicusa.com/tfx.htm). Make sure the size is the same. Edit: Which happen to be 21 A combined, I dunno.

You changed to a 5850?:shrug: Title says 5770.

That is the one I was looking at. I was also curious about a 5850.



Thanks for the info W1zzard handing to know that the numbers are after inefficiency. I found the data, but i switched my eye to the 5850 after seeing the figures for it.

After looking at anandtech's numbers for total system draw with the 5850 i may be cutting it too close. Granted his processor consumes more than mine.

[Theorw]

So with 9,3 amps max stock we can assume that when OCing this thing,say the consumtion goes to 150watts u l have 12,5 amps!Great energy saver!!!
U can safely up the consumption to 14Amps*12=168 amps!!!
I see great OC potential even for like 450w QUALITY psu!!!