PSU upgrade

Okay so im curious as to what I need to do. My m15x which is in need of a mobo has a 260m in it. As I've learned through this forum its a power hog and causes throttling issues quite easily/frequently. Do I just order an m17x adapter? or should I buy a different video card? im an Nvidia fanboy at heart. My desktop runs a 570 atm. Ati drivers blow and they are just dark imo.

 

The M17x's 240W PSU won't supply appreciably more power than the 150W unit because power draw is limited by the BIOS regardless of the source, but it will operate with less stress and cooler temps at the extremes. A different video card is the better solution. If you're a Nvidia fanboy, the most practical option is the 460M.

 

I wonder if you could bypass that. Or if it would be worth it.

 

Im just curious, ive read the 460m requires 72w? so how exactly would that stop throttling when the 260m requires 75? Looks like ATI may be the damn answer.

 

Don't know that it will, but it has been reported consistently in this forum that the 460M not only performs better, but also more efficiently than the 260M. Before switching to a 6970M, I used and prefer the 5850M, which almost never throttles and significantly outperforms the 460M, but you declared your devotion to Nvidia, which rules out the better choice.

Although tempting to imagine bypassing the limitations imposed by the BIOS power tables, they are there to protect the motherboard and its components from being fried by more power than it/they are designed to handle.

 

I am nvidia at heart, but at the same time reliability. I partly dislike ati because my 4890 quit 8 months after launch. Thus I like my nvidia cards that never die. Since I've heard such amazing things about this 5850 I would go for it. The 6970 would be a wet dream in my laptop, only because of the raw power on a portable pc. This has been a bad week for me. M15x mobo quits, and my 1200w es BFG psu quits. Hello $$

 

Sorry to hear about your troubles -- bad run of luck. Both the 6970M and the 5850M are great cards. The 5850M was made for the M15x -- strong performance and rock solid, although the Catalyst drivers will suffer glitches from time to time, usually corrected by the next release. But Nvidia's laptop drivers have suffered as well. Somewhat dubious video drivers are a fact of life for any high performance notebook so far as I have seen.

 

How much does either ati card run for ?

 

Here are some quotes I got from Dell in May (so that you can get an indea):

NVIDIA GTX 460m = Subtotal: $384.99 + Tax: $28.00 + Shipping and Handling: $15.00

AMD Mobility Radeon 5850 = Subtotal: $279.99 + Tax: $20.65 + Shipping and Handling: $15.00


You can find the AMD Mobility Radeon 5850 for around $200 - $250 outside of Dell

There is also the AMD Mobility Radeon 5870 and that goes for almost the same price of the 5850.

The member ichime is selling the Dell 5870 but you will need to use HWiNFO to control the fans as they will go at full speed without the program. Here is the link:

http://forum.notebookreview.com/com...n-mobility-5870-pulled-alienware-m17x-r2.html

 

By the way... since this thread title is about upgrading the PSU, I've got my 240W PSU today. Haven't done long tests so far, only some wprime 1.55 32M benchmarks, and I have to say it definitely helps. Not a single crash due to a power issue or PSU tripping.

I have my 920xm overvolted, at load 200mV more than usual, at a multi of 30x my kill-o-watt peaked at 216W.
With the standard 150W PSU it always tripped instantly when hitting 195-200W. Hope I can do some intense benching soon. Going to be interesting.

Maybe I can make the 240W PSU trip when I have the CPU and the GPU overclocked to the max, hahaha

 

Jesus, so the M15x can handle the additional 70 watts on the board? That's nuts.

 

At least it didn't die so far, hahaha

 

I thought this had been tested earlier and that it was confirmed that it wouldnt not go over 180-ish?

Thats a hell of a mobo you have svl7

 

Does it not effect the mainboard?, because the 240w PSU has more ampere than the 150W, could be not so good for the hardware or am i wrong?

 

Yes, you're right. Might not be very healthy over an extended period, but I'm not benching my system daily...

 

So, where and how are you increasing voltage to the CPU? How are you getting around the 920xm's 27x limit we have previously observed? 30x? -- on all 4 cores/8 threads? Wow, svl7, strange and wondrous doings in that lab of yours.

 

Here you go: Pushing an i7 920xm to new levels by increasing the CPU core voltage

I wrote a little summary about the process, it's a pinmod. You can also go less crazy and only increase 100mV or 150mV.
Heat goes up under load... will do some benches today when I find time. Haven't had the chance to do more than 32M wprime tests since I didn't have any cooling solution around.

Here's a 32M run at 28x, 144 BCLK (slightly more than 4GHz on all cores)

 

Is there another way? I don't really want to do pin modding. I just want to break the 27x mark.

 

There's no way to do it with software as far as I know.

There's another way to do it hardware-wise, but it's not easier... it's not a pinmod but a direct mod which requires some soldering at the mobo. You have to put a resistor between the voltage regulator feedback pin and ground. This allows to raise the complete voltage range for a few percent. Then voltage doesn't jump as with the pinmod.

 

Great!I have problems on M15x with 6990m
like shutdown suddenly
I guess maybe this problem will be solved if I changed a PSU
or its still a heat dissipation problem

 

Can anybody tell me where to buy a 240W PSU in China（220V） or in Canada（110V）

 

Just to clarify... there's no guarantee that the GPU can draw more power, so far I've only seen that it helps with the CPU. It's possible that the power draw through the MXM Pci-e slot is limited... I don't know.

The 240W adapter is called PA-9E, the 210W PA-7E, look on ebay or call Dell.

 

Fascinating business, svl7. Forgive the less technically adept, but if CPU voltage is the governing factor regarding multiplier limits, does the 940xm (which we know can sustain a 27x level in stock dress) have greater native voltage than the 920xm (with its stock 26x limit)? How is that implemented? Are the 940xm pin-outs different?

On the PSU front, in the absence of the pinmod, are you seeing any increased performance as a result of the 240W brick -- greater clocks for the 6970M and/or higher settings for the 920xm? I saw none after switching to the 240W, but always ready to learn a better way.

 

I'm not an expert when it comes to CPUs etc., but as far as I read in the Intel documents, it seems that every CPU gets the voltage programmed into it in the factory. It seems that each CPU gets tested separately and then set to a certain level. So it's possible that your CPU runs at a slightly lower voltage than mine, when sustaining the same multi/load.

I don't think the 940xm has generally a higher voltage, it is probably simply higher binned and thus capable of pushing a little bit more with the standard voltage, but that's only guessing. I've only measured the voltage of my CPU so far.
Making the the 940xm run at a clearly higher voltage would increase the power draw and heat extremely, thus I think it's very unlikely. They're probably at the same core voltage range as the 920xm CPUs.

The CPU voltage is very variable as you can see in the little summary I linked to earlier. That's pretty cool, it means there's no excessive power draw while idling. The voltage is set by the combination of seven different voltage identifiers, combined they cover a range from 0 - 1.5V, each step is 0.0125V...
The 940xm uses exactly the same voltage regulator (in fact the VR is on the motherboard, so it has to use the same) and it has the same "absoulte maximum rating" and the very same pin out as all 7xx/8xxQM, 9xx CPUs.

About the GPU: I haven't done any intense benching yet, but I'll do so in the next couple of hours. I'll see whether I can push it further than before, but I doubt it. The PSU seems to help with the CPU, but when I run vantage on the 150W PSU with the CPU at stock I had still headroom (power-wise) and wasn't able to push the card more. Well, I'll see whether I can crush some numbers.

 

Great thread so far. What the is with Dell telling me the 460m is 600 and the 5850 is 400+ meanwhile I see others got much cheaper qoutes?

 

Ok, after some big issues with my GPU clocks yesterday, I seem to have found a possible cause.

As soon as I start Throttlestop and raise the multi on all cores to 27 or more, my GPU clocks won't go over 400/900 anymore. I'm not 100% sure what exactly is causing this, I can only guess that there's somewhere a limitation on the mobo which reserves all the power for the CPU.

It's weird, my CPU peaked at almost 220W during some runs, there's definitely enough power available, but something seems to take away the power from the GPU, that's the only explanation I can find for the GPU clock drop. Maybe it would work with a slightly lower voltage increase, maybe 50-100mV.

So my guess is, that a PSU upgrade only helps for pushing the CPU above normal limitations. I haven't done any testing with the 240W PSU an standard CPU voltage, but according to The Rev and Inap it won't help.

 

My theory is that your M15x ain't stupid. It knows that if it lets you use the full power of the 6970M, you're going to start that benching business again and, sooner or later, you're going to try that 30x nonsense with a cranked up 6970M, and it wants no part of getting zapped again with 220W plus whatever the 6970M can bootleg in. It's in self-defense mode, and it's going to stay there until you disconnect that wire. Anything else you want to know about these computers?

 

Yeah what's its favourite ice cream?

 

Hahahaha Thanks!!