I'm in the process of upgrading various components on a ThinkCentre M55p (8811ECU) to use as my primary machine at work, and I bought a nice graphics card--GeForce 9600 GT 512MB-- and I realized after receiving it today that the power requirements (400W) exceed those of the existing supply. Thus, I'm debating either upgrading the power supply or just returning the card and getting one that fits the specs.

So my questions are as follows: how involved is a PSU replacement? (especially for someone who is not exactly a hardware expert), and secondly, if I decide to go with the secondary route, is there a video card that someone can recommend that fits the 310 watt limit of this machine? (I would ideally like an nVidia-based card, dual-head DVI with 512MB [although 256MB could be ok]).

thanks for any direction.

I have the same machine, I run an 8600 GT / 256MB DDR3. The box says it runs on a 350 watt power supply. I've had no problems with it. To the best of my knowledge, these are standard ATX power supplies.

thanks for your reply, Harry; I think I'm actually going to replace the power supply so I can keep this card and I'm wondering-- in shopping for a new PSU are there any crucial specs to which I should pay attention besides the wattage being at least the same as the existing unit?

Well, it sounds like you need at least a 400 watt power supply. Most modern ATX power supplies are fairly reliable. If you stick with the top names you can't go wrong; Enermax, Antec, Thermaltake, etc. You want at least 20A on the 12v rail too.

http://www.newegg.com/Store/Category.as ... r-Supplies

Here's a nice one -

http://www.newegg.com/Product/Product.a ... 6817371007

thanks again, Harry, very helpful-- btw what does the "12V rail" refer to? (this GeForce9600GT asks for 18A on the +12V rail)

It's the circuitry in the power supply that supplies 12v. The 18A spec is a minimum, if you go higher that is fine, in fact it is desirable.
http://en.wikipedia.org/wiki/Power_supply_rail

hi Harry-- since you have the same machine, I figured I'd throw one more question at ya: in addition to the video card upgrade, I also went ahead and maxed out the system memory to 4GB; I was surprised, however, to see only 2.99 reported in Windows system properties. I realize that certain chipsets prevent Windows from accessing the full 4 GB--as with my T60p--, but since PCDoctor reports that the max memory is 8 GB (in a 64-bit environment), I would think I'd be able to see the full four in 32-bit XP; any thoughts?

My opinion is that you won't see more than 3 to 3.4GB maximum addressable RAM in a 32bit operating system regardless of machine level capability.

Below is what I have. I don't believe I have more than 2GB installed in it so I can't test your problem, and I know it's not a chipset limitation;

Model M55P - 8811-DEU
Processor = Intel Core 2 Duo 2.13 GHz
Chipset = Intel Q965 Express
Max installed = RAM 8GB


http://www.intel.com/Products/Desktop/C ... erview.htm

Apart from the Server OSes, 32-bit windows cannot utilize more than 3 GB of system memory. You may want to refer to M$ Large memory support knowledge base article if you want to try implementing 4 GT and/or PAE in order to be able to address the full amount of installed RAM. But, to be honest, I don´t believe they will work under XP (even though there are plenty of articles and blogs recommending this "tweak").

Marin

thanks for the info guys... I'll have to take a closer look at attempting the GT/PAE mods;

here's something else on the power supply & video card question: I was actually about to purchase the PSU you referenced, Harry, and I noticed on the specs-- if I'm reading them correctly-- that the output is listed as 17A on the 12+V rail, and this card apparently requires 18A (and 350W)-- do you think this poses an issue? (these are somewhat uncharted waters for me, as I'm more of a software guy )

I quickly read the Ad and it said 20A (unless it was before coffee . Antec is a good brand, give them a call and see what they recommend.