GF 6600GT - Power Req's

[Tim Binns]

Hi there.

I'm running a pretty decrepit rig:

XP 2700+
Some Asrock MB or other
1 Gig no-name ram
Samsung DVD-ROM
Samsung DVD+-R/RW
2 x Samsun spinrite 200Gb
Some 3Com network card

This is housed in an Antec Sonata Mk 1 case.

Up until recently, I'd used a GF5900XT with no problems, but I thought
I'd upgrade this (the last upgrade for this rig - the next time I feel
the need for more speed, I'll be starting afresh with more up to date
components).

I put in a GF 6600GT, which has been problematic. About 1 boot in
three, I see the "Your graphics card is not getting enough power"
warning dialog.

Now the PSU in the Sonata MK 1 is a 380W afair which is supposed to
supply up to 16A on the 12v rail.

Looking at past threads in this and other groups, the collective
wisdom seems in agreement that 18A on the 12V rail should be regarded
as the bare minimum for those wishing to run the 6600GT. This suggests
that my power supply is marginal.

I've got first refusal on a second-hand, but unused Antec TruePower
II 550W PSU. The box has been opened, but the PSU has never been
installed in anything. This PSU has dual 12V rails, each of which will
push up to 18A. The asking price is GB£25.

Two questions:

1) Does it seem likely that my current PSU is marginal/insufficient
for my system now that I've installed a hungrier graphics card?

and if so,

2) Does the PSU I've been offered look like it will do the job? Is the
price fair? (NB. If the PSU is DOA or don't solve my problem, the
seller will take it back no questions asked - he's a good friend and
an all-round helpful sorta guy. Think "Ned Flanders" without all the
churchifying...).

advTHANKSance,

Tim.

 

[John Doe]

I put in a GF 6600GT, which has been problematic. About 1 boot in
three, I see the "Your graphics card is not getting enough power"
warning dialog.

A telltale sign if I ever heard one.

Now the PSU in the Sonata MK 1 is a 380W afair which is supposed
to supply up to 16A on the 12v rail.

My Antec 350 W supply has 21 amps at 12 V.

1) Does it seem likely that my current PSU is
marginal/insufficient for my system now that I've installed a
hungrier graphics card?

Yes, and AFIAK running a system with insufficient power is a bad
thing. In other words, I would be concerned about doing that.

Good luck.

 

[KC Computers]

XP 2700+

Some Asrock MB or other
1 Gig no-name ram
Samsung DVD-ROM
Samsung DVD+-R/RW
2 x Samsun spinrite 200Gb
Some 3Com network card
This is housed in an Antec Sonata Mk 1 case.
I put in a GF 6600GT, which has been problematic. About 1 boot in
three, I see the "Your graphics card is not getting enough power"
warning dialog.
Now the PSU in the Sonata MK 1 is a 380W afair which is supposed to
supply up to 16A on the 12v rail.

Did you attach a secondary power connector to the back of your video
card? I use the same 6600GT video card with a 20-pin 350W Enlight
ATX power supply with no issues.

 

[Tim Binns]

A telltale sign if I ever heard one.


My Antec 350 W supply has 21 amps at 12 V.

The 16A figure is from the data sheetfor the PSU at Antec's site.

Bear in mind it's the "quite" version with only one temperature
controlled 80mm fan.

 

[Tim Binns]

Did you attach a secondary power connector to the back of your video
card? I use the same 6600GT video card with a 20-pin 350W Enlight
ATX power supply with no issues.

Yup, the secondary power cable is firmly in the socket.

 

[KC Computers]

This is housed in an Antec Sonata Mk 1 case.

Yup, the secondary power cable is firmly in the socket.

It could be a flakey video card or power supply and it will be hard
figuring it out until you try a different one. From my experience
as a dealer, it's most likely the video.

 

[Tim Binns]

[snip]

It could be a flakey video card or power supply and it will be hard
figuring it out until you try a different one. From my experience
as a dealer, it's most likely the video.

Thanks for the professional insights.

I think I'll take the PSU and try it - it's a 20/24 pin design, so I
can use it in my next rig.

If that don't do the trick, I'll just have to RMA the card.

 

[johns]

I run 16 of those cards in PCs with SmartPower 350 watt supply.
Works great in AutoCAD, Solidworks, Rhino ... Far Cry. System
is AMD Athlon 64 3200+, 160 gig SATA, 1 gid ddr400 .....

johns

 

[John Doe]

The 16A figure is from the data sheetfor the PSU at Antec's site.

So, have you looked on the power supply?

Bear in mind it's the "quite" version with only one temperature
controlled 80mm fan.

I don't understand how being quiet has to do with supplying less
current at 12 V.

Good luck.

 

[Tim Binns]

So, have you looked on the power supply?


I don't understand how being quiet has to do with supplying less
current at 12 V.

Waall, I'm *guesstimating* that by removing the other 80mm fan from
the supply, they've reduced the available max cooling. The less
cooling you've got, the less current you can push through the PSU, no?

Just a WAG, and not really relevant to the discussion at hand in any
case...

 

[John Doe]

Waall, I'm *guesstimating* that by removing the other 80mm fan
from the supply, they've reduced the available max cooling. The
less cooling you've got, the less current you can push through the
PSU, no?

Not if you rate it the same wattage.

Just a WAG, and not really relevant to the discussion at hand in
any case...

I guess that's why you're not answering the questions. Knowing the
actual current rating is very relevant to the discussion at hand.
You should have looked at the power supply by now to tell whether
the actual current rating is greater than what you see on Antec's
web site.

 

[Tim Binns]

Not if you rate it the same wattage.


I guess that's why you're not answering the questions. Knowing the
actual current rating is very relevant to the discussion at hand.
You should have looked at the power supply by now to tell whether
the actual current rating is greater than what you see on Antec's
web site.

I've now got the psu on the bench, and yes, the sticker on the side
gives the same rated 12v amperage as the data sheet (16A).

That really helped me didn't it.

What do I do now, genius?

 

[John Doe]

I've now got the psu on the bench, and yes, the sticker on the
side gives the same rated 12v amperage as the data sheet (16A).

That really helped me didn't it.

Does a quiet power supply mean less power than its rating?

What do I do now, genius?

I would buy a power supply with enough power on the 12 V output.
Between now and then, I would remove/replace the video card that's
apparently draining your power supply and conceivably doing other
nasty things to your system.

I would guess your Antec 380 W is an old power supply that wasn't
intended to handle modern graphics cards. Being quiet doesn't mean
less power than its rating, it will probably source a lot of current
at the lower voltages. Unfortunately for you, new video cards run
off of the 12 V output so that's where you need the power for your
NVIDIA 6600 GT. Again, the newish Antec 350 W supply sources up to
21 amps at 12 V.