I have a Clevo P150SM with some pretty hefty overclocks (specs on my profile). My issue is that I want to upgrade my CPU and GPU in the near future and my 180 watt PSU is already pulling more power from the wall than its rated at (about 185-190 watts according to my Kill A Watt) when doing heavy work or gaming. I was wondering if just simply buying say a 300 watt power supply would allow me to have more power available to my future CPU and GPU?
PSU's are suppose to pull more power from that wall. The PSU rating is the power it can deliver to the device. If the power supply is 100% efficient, then it would pull 180w from the wall as well, but since power supplies aren't 100% efficient, they pull more power from the wall than they are rated, and the excess power is wasted as heat.
If my math is correct, assuming the power supply is 80% efficient, it can pull around 220w from the wall at full load, delivering 180w of power to the components, with 40w wasted as heat. Pulling 190w means your power supply is utilizing a little more than 150w, again, assuming 80% efficiency.
AFAIK - Laptop GPU's aren't swappable, and 180w about as powerful as they make PSUs for laptops. Last thing to note is the manufacturer likely designed the highest end configuration to pull well under 180w.
But, assuming you know something I don't, a new power supply would allow for more power, but the limit of the PCI-e standard is 75w, so GPU's tend to be under that, and CPU's aren't typically rated higher than 55w, so I'd assuming the appropriate VRM and auxiliary power connectors for higher rated parts would be absent, so power delivery to those specific components would still be limited.
Ok, thank you! Good to know that my power supply likely isn't maxed out yet. I will probably just upgrade my GPU and CPU and see if there is any power throttling and if my PSU is pulling a lot more power than before.
Only some laptop GPU's are upgradeable (ones with removable MXM form factor cards), the laptop's BIOS must support the specific GPU you want to upgrade to, (you can make that happen with BIOS mods) and the GPU's PCB and the laptop must be manufactured by the same company in most cases (Clevo and Alienware are interchangeable). My laptop does officially support the parts I want to upgrade to. (i7 4930mx and GTX 880m or 980m when released) The model that comes with those parts also comes with a 330 watt power supply so I just assumed that it would be necessary. I guess I will find out when the time comes for me to upgrade.
Well, I'd imagine the CPU upgrade wouldn't be the problem, but assuming you have the cooling, and BIOS support, I'd still have concerns about the GPU power requirements. The 765 runs the GK106 GPU while the 880 runs the GK104, which is significantly larger, with doubled the CUDA cores,TMU's, and ROPs, and the TDP spikes significantly. However, the similar P150SM-A that does run the 880 still ships with a 180w PSU, so I''d imagine it would be possible with that power supply (assuming all other pieces of the puzzle fit), but you'd be really pushing it, so you can forget overclocking.
I did think about heat, I have already installed full copper heatsinks (mine came with aluminium ones that had only copper heatpipes). The GPU was actually my least concern for heat, my 770m usualy stays around 65c and rarely hits 70c with my current overclocks, I am waiting for GTX 980m because Maxwell is supposed to have much lower power consumption and lower heat output, but if performance is similar to GTX 880m I will probably go for that for the reduced price.The Prema BIOS mod for P150SM (non A) does support the 880m and I emailed Prema and he said there is no reason he knows of that it will not be able to support the 980m in the future.
http://biosmods.wordpress.com/p1sm-changelog/
I am not aware of any significant difference between the P150SM and P150SM so I would assume that the internals are very much the same if not identical. I know that when configuring my laptop there was an option for a 4930mx and 780m and as the 880m is basically a 780m with more VRAM and higher clocks I would imagine my laptops internals are perfectly capable of dealing with those higher TDP components.
Funnily enough the TDP of a 4930mx plus a 880m is exactly 180 watts, and add 10 or so for RAM, SSD's, HDD's ETC and its over what my PSU can supply. So unless the 980m has a lower TDP I would need a higher wattage PSU or decide between a CPU or GPU upgrade.
So theoretically a larger PSU would allow my laptop to use more power if it turned out that future upgrades will require it, assuming the PSU was the same voltage and had the same connector.
Thanks for correcting me, the P150SM-A does come with a 180 watt PSU, I must have mistaken it for a P370SM or something that comes with a 330 watt PSU.