Overclock3D improves its PSU testing equipment

2009 - Year of the PSU!

Overclock3D improves its PSU testing equipment

Back in April of 2006 , Overclock3D embarked on it's first PSU review. Determined not to go down the "plug it in, take some readings" route, initial load testing was performed using a carefully selected assortment of high wattage lightbulbs to place heavy loads on the +12v rails. It soon became clear that this setup was far from idea with the fragility and heat of the bulbs posing serious safety issues along with a total inability to test the +3.3v and +5v rails or make small adjustments to the load settings.

This setup was quickly replaced by a series of power resistors capable of placing loads on each of the three main PSU rails (+3.3v, +5v & +12v) while also allowing load adjustments of around 5 amps on each of the rails simply by adding/removing resistors from the circuit. For almost two years this became our main testing platform with various improvements being made over time including the ability to place up to a 100 amp load across several rails along with loads of up to 40 amps on the +3.3v and 5v rails. The entire system was encased in a large steel box complete with high power fans and CPU heatsinks on each of the power resistors to help keep under control the 230°C temperatures that they could reach when not actively cooled.

Unfortunately (or maybe fortunately?) in July 2008 the cooling system in the load tester was accidentally switched off during the testing of a PSU and the entire system subsequently overheated and went 'BANG'. Since then we've avoided performing any PSU reviews (apart from the odd one or two performed at Enermax's old Milton Keynes offices) until we could obtain a professional ATE load tester that would help us take our PSU reviews to the next level. Today that very item arrived on our doorstep:

SunMoon SM-268 ATE SunMoon SM-268 ATE

SunMoon SM-268 ATE On SunMoon SM-268 ATE On

Seen above is our brand new SunMoon SM-268+ ATE load tester capable of placing a sustained load of 1690w across a total of six rails (including +5vsb and -12v) on any ATX PSU. Unlike our previous resistor based load tester the SM-268 gives us the ability to adjust amperage loads in increments as small as 0.01a while also measuring voltages and wattage readings on-screen. When connected to a PC the SM-268 has a full software suite that can effectively remote control the unit, making fully automated testing possible while also being able to output the test results to a printer.

Of course, having only spent one day with the SM-268 so far we're still really getting to grips with what it's capable of, and with an Oscilloscope on its way down to us too, it's certainly going to be a steep learning curve. However, over the next few weeks we will perfect and document our new PSU testing procedures and begin bringing some of the most accurate PSU reviews to your screens!

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Most Recent Comments

07-01-2009, 19:29:52

I completely understand what you mean mate,

But I live in New Delhi and here the GFX cards are double the price of US/EU.

When I got my MSI 7600GT It was for the same price as a 8800 lol!
And also because this is just a warranty replacement for the 7300, I have no other choice :)

I'll be visiting Singapore soon so I'm thinking of getting a G25 and a GFX card from there (If I'm able to get universal warranty on it)

I already own a G9 and G15, some things here are almost the same as other markets but that's very rare... I had to wait for a month to get my Stacker 830 and it also cost me double the list price.. Ouch!
I would have already got the Acer G24 last year but its not available here, I called the Acer headquarters and someone there even asked their seniors about shipping one here in a meeting but its not possible -_-

I can go on and on and on about this haha!

07-01-2009, 19:35:58

In that case looks like your stuck with the 7900. To be honest, a card like that can happily run oblivion at high spec with decent frame rate at 1024*768 with a much worse processor, so you should be fine with it (unless you try to run crysis, then good luck)

07-01-2009, 19:48:07

Lol yea!

So that's it then, get the XFX 7900GS instead of a XFX 8400GS right?

If it was possible to get universal warranty on a GFX card then I would have just ordered a 9800 or something from Amazon etc. any day!

Actually I did try to run Crysis on 7600 and it really worked, not even on the crappiest settings but I had to keep the resolution to 1024x768 on a 19" monitor.
It only crashed when I tried to turn on AA, it just wouldn't let me do it... And everything whet SLOW Motion lol.

COD4, Grid, Ghost Recon Advanced Warfighter 2, rFactor all work pretty fine on the 7600...
I just have to compromise between the resolution or the graphic settings, low graphics = full resolution OR ok graphics = 1024x768 resolution.

Thanks for the help, I really appreciate :)

08-01-2009, 06:38:26

Looks like you've got your mind made up but I'll just say the 7900GS gets another vote from me, had it in my rig till last month, it's a corker for source games, so HL2 Ep2 and TF2 run great on it.

Also the XFX one OCs really well (it's the one I have) and if you whack an aftermarket cooler on there you can push some pretty big numbers/frames. :)

08-01-2009, 07:04:13

The Zalman GPU cooler doo-dah fits nicely on it, I had one of mine til it blew up somehow. If you are looking to replace the stock cooling I recommend these, might even get rid of mine as the cooler on my 4670 is fairly quiet most of the time

08-01-2009, 07:07:51

Or the Akasa Vortexx Neo... but you will have to cut through your card to fit it LOL (XFX has a non reference barcode thing on the bracket), so the zalman is probably better!

08-01-2009, 12:07:57

Thanks for the help guys!
I have to call them tomorrow to confirm which card I want...

Is 7900 really that noisy? I did read the reviews on few websites and they all noted this but is it any louder than my MSI 7600GT?

Look for photos of the MSI 7600GT on the internet and compare its fan with the 7900 and 8400.

Also please search on google for :
cnet XFX GeForce 8400GS - graphics adapter
and open the second link from top...
They say its all ok :rolleyes:

Seems like the MSI7600 has a much better cooling system than the 7900 and 8400?

Still not sure, the 8400 looks tempting :yumyum:

08-01-2009, 12:22:11

The 8400 is a mainstream card, which seems stupid to combine with the tech you have under the hood of your computer. The 8400GT will be noticeably worse than the 7600GT. The 8400 is designed to be cheap and cheerful and is not designed to have loads of hispec games to be chucked through it.
The cooler (I assume it will be very similar to the one found on the 7800GTX I have on my second rig, because it looks very similar) will not be very noisy. The only issue is that if you want to heavily clock this card, you will want a 3rd party cooling arrangement same as any other card.
I would go for the 7900 or ask if there is a better 8 or 9 series you could go for.
Just for reference the 8400Gs is several tiers behind the 7600GT, which is one tier behind the 7900GS ([url]http://www.tomshardware.com/reviews/best-graphics-card,2118-7.html[/url]). I think that link ought to explain everything.

08-01-2009, 12:28:43

The 7900GS uses the same cooler as the 7600GT, and then I think a few places done after market coolers, but in my opinion it is too noisy, so I opted for a CU900 or whatever it is.
I would get the free upgrade to a 7900GS and then consider the likes of the Akasa Vortex or Zalman CU900 for it if it is too noisy, mind you it is temp controlled so only kicks in when you ramp up the activity. The standard cooler just appears to be a place of copper with a fan and a few fins, I would not trust that too cool it too well to be honest.
Trust us, the 8400 is not going to do your system any favours apart from being low power consumption, looking at your spec you will like the 7900GS lots :D It is basically the high end 7900GT with a few clusters disabled but still a hell of a card

08-01-2009, 13:42:40

Hey guys thanks a lot! ^^

I'll go with the 7900GS then!
Will look for an after market cooler later when I think its time to overclock lol.
I usually don't do any overclocking, my 7600 is already overclocked and the 7300 can go upto 512mb so it doesn't make much difference...
I guess I'm saying this because I have very crappy gfx cards :P

I'll update here soon :)

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