Hd 7750 Low-Pro: too much power?

Fedecks

Honorable
Oct 11, 2012
9
0
10,510
Hi, I am looking to upgrade a manufactured micro-ATX system, an acer aspire X3400G. I'm looking to add a stand alone graphics card, as this one didn't come with one and the onboard 9200 is a pinch point atm. I'd like it to run games rather well. Currently, I am looking to buy a low-pro powercolor HD 7750 (http://www.newegg.com/Product/Product.aspx?Item=N82E16814131480) for it. It already has a 4gb ram upgrade (bringing the total to 8gb).

My problem is that the product "requires" (according to amd "recommends") a 400w power supply. This system ships out with an abysmal 220w power supply (http://support.acer.com/acerpanam/desktop/2010/acer/aspire/AspireX3400G/AspireX3400Gsp2.shtml). Id really like to not have to pay double to get a new psu too. This system does ship out with GPU's, most of which have the same 400w recommendation. However, most of them have a max power draw of about 43w. I can't seem to find the spec for the 7750, so I have to assume its around 70w (the output of the pcix 2.0), but then again I've come across an article which measured it at a peak of 43W under load (http://www.techpowerup.com/reviews/ASUS/HD_7750/24.html), so I'm not quite sure. I really want that card, but I'm afraid I might not have the power. Then again with that as a peak measurement, and the difference being so little, I'm thinking I could get away with it.

Since I've always sided with a good size psu, I was hoping I could get some input. Would I be crazy to try this or should I go for it? What consequences could I incur if the psu isn't up to it? Anyone have experience with this kind problem?
 

JJ1217

Honorable

Fedecks

Honorable
Oct 11, 2012
9
0
10,510
Thanks, thats what I was thinking. It just wont boot up then if the psu is too weak?

Also thanks for showing me the sapphire. I've used a sapphire card before and had good luck with em, didn't know they made a lp 7750 as well.

About the power supply though, is that gonna fit? I thought the form factor for micro-atx psu's was different.
 

kevin83

Distinguished
Apr 27, 2011
437
0
18,860
In your situation it seems the best course of action would be to try using the 7750, and in the event that it can't boot immediately stop trying to boot it and buy a new one.
In the event that your power supply really is micro-atx based (you should check to make sure it isn't mini-itx factor) then you're looking at this power supply as a replacement, it's the only one on newegg that even meets 80+ bronze....
 

need4speeds

Distinguished
It should boot up.

The card uses very little power when booting up and running windows.

It will use more power when playing games however, if games artifact or crash because the card is short on power that is when you will know.

I think the card will run fine, they use about 60 watts under full load.

What cpu do you have? The link you gave shows it can come with a range of am3 cpus. This does matter somewhat. If it has the top model phenomII x4 that cpu is 125 watts and will eat up most of the power.
If you have the athlonII x2 or lower wattage athlonII x3 or x4 then you have some power to spare.
Since the board powers the card through the pcie slot, the cpu also shares this power.

They show a hd-5570 card and a geforce 320. Both of those cards use at least as much power as a hd-7750, so if they were running them on that power supply, i am pretty sure the hd-7750 will also work ok. I suspect they don't pair the phenomII x4 965 or 955 with these cards and opt for the athlonII's or lower wattage phenomII's instead.

 

Fedecks

Honorable
Oct 11, 2012
9
0
10,510
It's an athlon II 255, looks like its rated at 65w. I'm hoping that will give me leeway. Any idea what 4gb 1333 ram would suck up (if anything substantial)?

Also at kevin83, looks like it actually is a mini-itx, so thank you.
 

need4speeds

Distinguished
That's a good thing. It sips power and runs nice and cool. The athlonII 255 has a 3.2ghz clock with 1mb cache per core. It's actually a decent gaming cpu for a dual core. I paired my friend's athlonII 250 with a used hd-4870 and it plays games really well at 1080p. It's a bit faster than the slower clocked athlonII X3's and X4's for gaming because it has 1mb cache per core vs. 512kb and a much higher clock speed. My friend was actually playing Crysis on it at med settings with over 30fps. Cod black ops ran but had some slowdowns but was playable. Skyrim ran ok on it. The hd-4870 and hd-7750 are pretty close in speed.

Don't forget the integrated geforce 9200 gets disabled once you add a discrete pcie video card to it. The integrated geforce 9200 is actually kinda a power hog for how slow it is, the integrated gpu probably uses about half of what the hd-7750 used under full load anyway.

You might have to disable it in the bios, and enable the pcie card in the bios, but most boards do that automatically.

You have power to spare actually and should be able to overclock the hd-7750 since they are known to be good overclockers.

Adding a case fan somehow would be smart, and don't forget to blow the dust out of your cpu heatsink.

Memory uses very little power maybe 1 watt per stick.

Well anyways good luck i hope it all works out.