Let's look at the TDP for the 520 1GB.
" NVIDIA gives the GT 520 a TDP of 29W, while we’d expect the idle TDP to be around 10W."
http://www.anandtech.com/show/4268/nvidia-releases-geforce-gt-520
That's no where near 300 Watts so the 300 is the total system that they would call out to make it easy to figure out.
There's usually no call for 4GB GPUs for most folk. More RAM there is not more speed. And there is no 4GB short video card out there (this may change with time.)
http://www.anandtech.com/show/7764/the-nvidia-geforce-gtx-750-ti-and-gtx-750-review-maxwell/4 notes a 55/60 Watt GPU that might be a candidate but I would put the machine on the Watt meter first. I use this one.
https://www.amazon.com/P3-P4400-Electricity-Usage-Monitor/dp/B00009MDBU
That way I know what the total machine is drawing and if there's room.
I want to upgrade my GPU.
Currently I am running a Nvidia GeForce 520 1GB Card
My issue is power requirements. According to Nvidia, my card (which has been operating fine for 5 years) requires a power supply of 300 watts. Upon opening my desktop, my power supply has a sticker which states " MAX POWER 220W"
The GPU's I have been researching require at least 300 to 400W. My question is: How has my GPU been operating with a lower rating than required? My computer is an HP slimline ( more info if required is at request) I feel I do not have room more a larger supply nor to I feel qualified to replace one. I would like to run anything from 2GB to 4GB GPU
Thank-you in advance
-Mike
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