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Carrizo FX-8800P, A10-8700P Info and Optimizations - Page 2

post #11 of 314
Thread Starter 
Yeah, I remember The Stilt saying something about RAM speed being limited at lower cTDPs... I'm definitely hoping The Stilt or someone else will figure out a way to change TDP.
post #12 of 314
Quote:
Originally Posted by jrs3000 View Post

With it being limited to 15w, it only uses 1600mhz max it seems. I tested it with 2133 sticks in it and reran dirt 3 bench, no change. I also checked cpuz and it didn't show it at the higher speed. If someone manages to find a way to change tdp to 35w then faster ram can be used. This laptop has potential but Toshiba and other OEMs neutered the top chip to 15w so it can't shine mad.gif

Even if you magically unlock cTDP, you won't automatically get RAM speeds past DDR3-1600. That is because one of the very first things the BIOS/start-up code performs on memory controller after power-up is calibration/training at specific memory clock frequencies (calculating +/- timing offsets for various DDR3 control/data signals) to ensure that during normal operation all control and data signals integrity/timings conform to the JEDEC specification. So if BIOS is only coded to train the memory controller up to DDR3-1600 (800MHz) then that will end up the highest available DDR3 clock frequency irregardless of the unlocked cTDP.

It's way more work than just flipping a switch on cTDP to get faster DDR3 speeds, BIOS code needs to be modified. And on a top of that different OEMs have different BIOSes. Without BIOS source code it's going to be nearly impossible to hack this up for one specific system, let alone several systems. There is AGESA library source code available (http://review.coreboot.org/gitweb?p=coreboot.git;a=tree;f=src/vendorcode/amd) but it's just a library meant to be combined with OEM-specific BIOS source code.
Edited by logiotek - 9/18/15 at 7:38pm
post #13 of 314
Thread Starter 
There seem to be some reliability issues with the wifi in the Radius 14, hopefully this is a matter of a few bad units vs an actual issue with the components selected by Toshiba. Given the estimated difficulty in changing both the cTDP and RAM clocks, I think I'll be waiting for the Y700 to be released before making a final decision. I suspect that the Radius 14 would offer all the power I need, but there's something about knowing that the hardware is being limited that bothers me.
post #14 of 314
Quote:
Originally Posted by logiotek View Post

Even if you magically unlock cTDP, you won't automatically get RAM speeds past DDR3-1600. That is because one of the very first things the BIOS/start-up code performs on memory controller after power-up is calibration/training at specific memory clock frequencies (calculating +/- timing offsets for various DDR3 control/data signals) to ensure that during normal operation all control and data signals integrity/timings conform to the JEDEC specification. So if BIOS is only coded to train the memory controller up to DDR3-1600 (800MHz) then that will end up the highest available DDR3 clock frequency irregardless of the unlocked cTDP.

It's way more work than just flipping a switch on cTDP to get faster DDR3 speeds, BIOS code needs to be modified. And on a top of that different OEMs have different BIOSes. Without BIOS source code it's going to be nearly impossible to hack this up for one specific system, let alone several systems. There is AGESA library source code available (http://review.coreboot.org/gitweb?p=coreboot.git;a=tree;f=src/vendorcode/amd) but it's just a library meant to be combined with OEM-specific BIOS source code.

Gotcha. Well looks like I'm going to return the ram and laptop and wait for a 35w to show up. I'm seriously doubting anyone will put 35w in a 13"-14" mad.gif
post #15 of 314
Quote:
Originally Posted by jrs3000 View Post

Gotcha. Well looks like I'm going to return the ram and laptop and wait for a 35w to show up. I'm seriously doubting anyone will put 35w in a 13"-14" mad.gif

What 2133 MHz RAM did you get? Specs? Cost? Why not just keep the RAM if you plan on acquiring 35W Carizzo?

I did a quick search and Amazon has a Kingston 2x8GB 2133 MHz kit for $114.99. I haven't found anything cheaper than that. I would prefer Corsair RAM but cost to benefit just doesn't add up.
http://www.amazon.com/gp/product/B00NTQ0GOM?psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=AVGGEPEO9L187

Lastly, a 35W Carizzo can fit into 11.6" form factor comfortablly wink.gif, 15W 10.1" and up to 14" 35W. However, we rarely see these sizes, we get 15.6"-17.3", at 15W too tongue.gif because they apparently sell better. Hm, okay! I'll be satisfied just to have 35W Carrizo at this point... rolleyes.gif
Edited by davidricardo86 - 9/20/15 at 2:10am
post #16 of 314
Thread Starter 
I would also recommend keeping the RAM as the Y700 has 1600 MHz from Lenovo. I plan to spec the best dGPU but leave the other options at base levels. That way I can change out the RAM and HDD with the parts I want.
post #17 of 314
The Stilt,

Tomorrow I take delivery of an Acer Aspire E 17 with an FX-8800P/R8 M355DX combo - http://www.saturn.de/mcs/product/_ACER-Aspire-E-17,48352,2044268.html. I fear it is limited to 15 watts. Acer needs to explain why they would limit a 35 watt APU to 15 watts then add a less potent 25 watt dGPU (384 shaders as opposed to 512 in the iGPU. Although I'm still encouraged to think that the R8 might be more potent than just 384 shaders; and I quote: "In addition to the integrated graphics unit with 512 shader units still comes a Radeon R8 M355DX used. "DX" GPUs act according to experience to Dual Graphics solutions, where the dedicated GPU cooperates with the internal. The R6 255DX was based on Topaz / Oland with 384 ALUs, the R8 indicates at least that the M355DX could turn more powerful - conceivable would be a slimmed Cape Verde, also with 512 ALUs. (sic)" This is a (poor) translation from a German website - http://www.pcgameshardware.de/Notebook_Laptop-Hardware-201330/News/AMD-Carrizo-FX-8800P-1160071/

Anyway, a boy can dream.

I just makes absolutely no sense. Anyway, it comes with 8 GB of DDR 1600 and a 90 watt power supply, so, I'm just not sure. Anyway, I will likely need your cTDP app. I'd even be willing to pay. If not I'm out $800.00 for a neutered computer that is incapable of even playing GTA V. I don't have much money. I am disabled, so... Anyway, I would like to thank you in advance for your anticipated cooperation.

Sincerely,

Erik
post #18 of 314
Quote:
Originally Posted by ecstubblebine View Post

Acer needs to explain why they would limit a 35 watt APU to 15 watts then add a less potent 25 watt dGPU (384 shaders as opposed to 512 in the iGPU.

Easy to explain from OEM's perspective. Easier to cool 15W and 25W dissipated spread out across 2 points (2 chips) than 35W concentrated in a single point. Also by including any dGPU it sounds better from sale's perspective as most people associate any dGPU to be better performance than any iGPU.
post #19 of 314
Based on how Toshiba, Acer and HP have built their Carrizo laptops I think there is a very slim or non-existent chance I can release the tool to adjust the cTDP rolleyes.gif

The cooling and the VRM on most of the Carrizo laptops seen so far is absolute garbage, and increasing the power consumption and thermals any further would put the systems in severe risk.

There are way too many unknown variables (VRM, cooling, power brick, presence of dGPU) which can have a huge effect on the outcome and because of that increasing the TDP limit is anything but safe.

I think there are only two systems which can even remotely safely handle the 35/42W cTDP configuration: AMD reference system and Lenovo Y700-15ACZ. Even the AMD reference laptop despite it´s beefy VRM and dual cooling system cannot handle 35/42W continuously, as the VRM will reach the temperature limit at some point.

Based on what I´ve heard, most of the ODMs use systems originally designed for Carrizo-L (Mullins) for Carrizo too.
Since Carrizo-L is rated up to 25W only, limiting the TDP to 15/25W on Carrizo too makes some sense.
Edited by The Stilt - 9/21/15 at 1:35am
post #20 of 314
Thread Starter 
Good to know, thanks for the info. I think I'm going to go with the Lenovo Y700 when it comes out. For those that do choose to go with the Toshiba Radius 14, would there be any optimizations that could be made via software tweaking? My C-60 became a lot more usable after I installed and configured BrazosTweaker.
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