Higher Consumption on PSU Upgrade?

[dcproulx]

Hello everyone, my first post although I've been lurking for years. 😉

I'm getting ready to upgrade my HTPC, to start I upgraded my PSU from an Allied AL-8250SFX that came with my old MI-008 m-itx case, to a Corsair CX430 (I know, but hey, $25?) in my newer Silverstone ML03. I was rather surprised to see the idle power jump from 28w to 34w, and load from 51w to 73w, that is with the optical drive now removed (it won't fit, going external to save power anyhow).

The question that is really bothering me is, what was not getting juice before the upgrade? Is it just that the new psu is underutilized (for now) and is therefore not as efficient? Or was something being underpowered the whole time I was using the system? Was I inadvertently underclocking my cpu? Was that why my memory always seemed to be wonky? And on my PC too?

Once I upgrade, I'm sure the psu will be more efficient, I don't think the old one would power my new build, or if it did, it would be stretched. Feel free to comment on that, and on my new build if you want, I'm open to suggestions! Thanks!

btw, I was originally looking more for a psu in the 300w range, but I just couldn't resist this deal.

Allied:+5V/+3.3V: 115W, +12V:192W Corsair: :+5V/+3.3V: 110W, +12V:384W

Old Build:

Case:Apex MI-008 m-ITX
PSU: Allied AL-8250SFX
MB: Zotac GF9300-D-E m-ITX LGA775 GeForce 9300
CPU: Intel Pentium Dual Core E5300 2.6GHz 2MB 800FSB 65W
RAM: OCZ Platinum XTC REV.2 PC2-6400 4GB 2X2GB DDR2-800
HDD: ADATA AS510S3-120GM-C 120GB
WD2002FAEX Black 2TB Sata2 Ser#WMAY01069199
Other: LG GGC-H20L BLU-RAY/HD-DVD
Belkin F5D8053 N Wireless Draft N 802.11N USB Adapter
Scythe YD-8V08 18-IN-1 Floppy Disk Drive and Card Reader C

New Build:

Case: Silverstone ML03
PSU: Corsair CX430 "V2"
MB: AsRock FM2A75 Pro 4
CPU: A10-5800K or A8-5600K
RAM: 8GB DDR3 1600
HDD: same for now
Other: LG GGC-H20L BLU-RAY/HD-DVD (via eSata, heh heh!)
Belkin F5D8053 N Wireless Draft N 802.11N USB Adapter
Some fancy 5 1/4 drive bay device w/card reader, LCD?

 

[BFG10K]

PSUs are generally most efficient at 45%-55% loads. Also higher wattage PSUs tend to use more power than lower wattage PSUs at very load loads (e.g. an idle rig).

So if your second unit has a higher capacity than your first unit and both have roughly equal efficiency, what you’re seeing is normal.

This is one of the reasons not to get a totally overkill PSU for your needs, though obviously not everyone is concerned about this fact.

 

[blastingcap]

Rightsize your PSU with a high-quality PSU of the appropriate wattage and you will have higher efficiency = pays for itself. The best Gold/Platinum PSUs are so efficient that there isn't even much of a PSU fan noise penalty because so much energy goes into DC power that there isn't as much left over for the PSU to dissipate.

Or you could follow ancient "advice" from posters following ~2002 "common wisdom" and get oversized PSUs "just in case" and suffer lower efficiency AND get to pay more for the privilege.

 

[dcproulx]

OK, thanks, I guess I got carried away by the deal and over sized. :-(

I'll look for a more efficient unit in the 300w range. Thanks!!!

 

[TemjinGold]

I would just keep what you bought. The difference in savings is nearly nonexistent at those loads.

 

[dcproulx]

I'm going to use it with the new build, if I'm not happy, I'll go looking again. It's really just a few watts, so yeah...

Thanks!