What happens when I adjust SPD values?

[kokolordas15]

Hi, I am experienced with normal ram overclocking/tuning via BIOS and i have 2x16GB micron R-die 2x8R on my 4800h+1660ti legion laptop. Say I enter unstable/unbootable values on the SPD for the 3200bin what happens next? Will the laptop enter "safe mode" and boot the 2133 bin or i am fcked and will have to maybe flash the SPD ROM with a hardware flasher?

 

[EarthDog]

Are you coding these values in, or making simple adjustments from the BIOS? If the latter, then yes it will fail and reset. If you're reprogramming the SPD, you would want to make sure whatever your're hardcoding in actually works FIRST. If the system defaults to that then it would reboot loop. If you change the XMP, and leave the other JEDEC stuff alone, it will fail over properly.

 

[kokolordas15]

Are you coding these values in, or making simple adjustments from the BIOS? If the latter, then yes it will fail and reset. If you're reprogramming the SPD, you would want to make sure whatever your're hardcoding in actually works FIRST. If the system defaults to that then it would reboot loop. If you change the XMP, and leave the other JEDEC stuff alone, it will fail over properly.

https://www.overclockers.com/forums...M1PXP-ncZUDQO8ajDkHwL9sbp1Wx_BGXfcEQx_9cNYO7E

I clicked quick reply to the thread i link above but it somehow made a new post. My bad

- - - Auto-Merged Double Post - - -

I am new to this forum and I don't know how to delete this thread. If you want feel free to delete to avoid spamming the section. Thank you

 

[EarthDog]

I moved it here to its own thread. Did you have you have those specific patriot sticks in the thread you posted in? The question seemed kit agnostic so I moved it from the thread that talks about the patriot kit to your own.

EDIT: I see you reposted in the other thread, lol! I deleted that post too. If we figure out here that it should be in that thread, I'll add it back. But this seems like a generic question about what happens when you adjust SPD values so far...

EDIT2: Please post CPUz screenshots (you do this in advanced posting, not quick) that show the SPD tab for the stick as well.

 

[kokolordas15]

I moved it here to its own thread. Did you have you have those specific patriot sticks in the thread you posted in? The question seemed kit agnostic so I moved it from the thread that talks about the patriot kit to your own.

EDIT: I see you reposted in the other thread, lol! I deleted that post too. If we figure out here that it should be in that thread, I'll add it back. But this seems like a generic question about what happens when you adjust SPD values so far...

Yep the question is a generic one but kind of applies to his setup given that its similar to mine. Basically the way i saw it Woomack has likely gotten himselft into unstable SPD timings on the 3200 bin and want to see how he overcome that. Since the kits have multiple bins from 2133 and above then maybe it will fall back to a slower one if the highest one is not training.

If thats the case I am not afraid to go ahead and tune the ram this way with thaiphoon burner

 

[EarthDog]

So, you're actually overwriting the SPD values, not simply BIOS adjusting? Doesn't sound like something that should be done for a simple laptop... but maybe that's just me. Performance gains are nill and this is a change that could potentially bork things. At least with adjusting in the BIOS you know it will automatically revert back. But if you're messing with the base profile, that's scary to me (especially for little to no gains).

Can you please post some pictures of the SPD tab for your kit? I'm sure Woomack or our other memory peeps will stop by.

 

[mllrkllr88]

I am not exactly sure what you are asking, but here's my take on it...

You can easily reprogram the SPD IC on your laptop memory via the Thaiphoon Burner tool. If you pay the $50-ish for the unlocked version, you can simply search the huge database for an XMP that suits your needs, and reprogram your memory. The whole process is done in 10 seconds if you know what you're doing. However, there's no reason to do this if your motherboard has memory overclocking capabilities. If your motherboard ONLY allows you to set XMP and not edit anything, then it's worth a shot. In terms of stability, it's exactly the same as overclocking. Meaning that if you flash a junk 3600c18 Hynix kit to 4800c19 Samsung, the XMP profile will fail train and it won't run, but the motherboard will see it as 4800c19 XMP.

I went deep down the SPD rabbit hole myself and I learned a few interesting things.

1. Reprogramming the XMP is the same as overclocking. If you take a 3200c16 kit and reprogram the SPD to show 3600c16, it's the same as if you simply overclocked the frequency.
2. You can create crazy custom XMP profiles like 4133 CL12-12-12 @ 2.05v and it works flawlessly (with appropriate hardware)
3. Not all timings are the same. Have you ever wondered why one company is consistently 'faster' than another at the same speed? If you dive into custom SPD you will find out that for each timing there is a range of latency options (usually 3 speed options for every timing). It gets advanced, but you could have a slow 14-14-14 or a fast 14-14-14 based on the 'secret' latency options for each timing. These are invisible to the user and the MB does not show them. The only way to see them is to dive down that rabbit hole...
4. Reprogramming the individual timing latency does increase performance for the XMP, but it's very marginal and definitely not worth the time ~<1%

...Next time you buy used memory, make sure it looks correct and the XMP profile matches the sticker

 

[kokolordas15]

SPD readout from thaiphoon,the kit is crucial CT2K16G4SFD832A

These laptops don't have XMP support so you are stuck with JEDEC timings/voltages. The 4800h will run 3200MT/s and whatever timings the kit has for the 3200MT/s bin. Since im stuck with no XMP support and voltage control only thing I can do (like Woomack did) is to find the best possible timing configuration at 3200MT/s while using just 1.2 Volts on the dram. I am familiar with ram overclocking and it is fun for me to spend a week tuning ram to its limits so thats not an issue for me but if I am going to do it this way I would like to know what the Plan B is from Woomack or someone that has done this before. If the AMD AGESA is smart enough to attempt slower bins once the 3200 fails(if i enter too aggressive timings) instead of trying the same thing over and over then its game time for me.

 

[EarthDog]

SPD tab from cpuz, please. I'm curious to see how many profiles it has.

Are you able to select different profiles at all? If not, then this is a longer trial and error process as you'll have to reflash each time unless you know some stable settings. JEDEC is the most basic and what it will pull. The 2q33 timings are pulled from the stick. If that's changed, I dont think the system figures it out...

Buy 3200 MT/s SODIMMs that are native 3200? But then those timings are typically super high...

 

[Woomack]

I recommend you to program memory sticks one by one and when one of them runs without issues then you program the other one. This is because when you set too tight timings then the laptop won't boot at all and will show a memory error. There is no second, lower SPD profile. You can still boot it on one stick and "hot plug" the 2nd stick. Thaiphoon Burner will see both sticks and you will be able to flash the "bricked" one too.

This is a short guide:
1. Check if your RAM has unlocked SPD - if it's locked then you can't program it with software - Thaiphoon Burner, even the free version, can check it
2. If SPD is unlocked then start from JEDEC profiles which you can pick from the list in the SPD editing window - the tightest JEDEC profile is 3200 22-22-22-52 1.20V
3. If you make any SPD profile run then drop timings one by one and run stability test for like 15 mins. For example when you make it boot at 3200 CL22-22-22 then try CL20-22-22, then 20-21-21, 20-20-20, 18-20-20, 18-19-19, 18-18-18 ...
4. Don't even try more than DDR4-3200, it won't boot on most laptops or at least those without XMP as AMD controller runs at default DDR4-3200 max.

If you set too tight timings and the memory stick won't be able to boot then start the laptop with the good stick properly installed and the second one in the slot but not locked. Once the laptop boots, push the stick that can't boot on itself, so it locks in the memory slot, and it will be visible in the windows. This is somehow risky.

 

[kokolordas15]

I recommend you to program memory sticks one by one and when one of them runs without issues then you program the other one. This is because when you set too tight timings then the laptop won't boot at all and will show a memory error. There is no second, lower SPD profile. You can still boot it on one stick and "hot plug" the 2nd stick. Thaiphoon Burner will see both sticks and you will be able to flash the "bricked" one too.


If you set too tight timings and the memory stick won't be able to boot then start the laptop with the good stick properly installed and the second one in the slot but not locked. Once the laptop boots, push the stick that can't boot on itself, so it locks in the memory slot, and it will be visible in the windows. This is somehow risky.

This is the info I was looking for. Thank you for your time everyone!

 

[EarthDog]

Please keep us posted on the result!