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Crucial DDR2 JEDEC

Joined
Mar 21, 2021
Messages
5,544 (3.62/day)
Location
Colorado, U.S.A.
System Name CyberPowerPC ET8070
Processor Intel Core i5-10400F
Motherboard Gigabyte B460M DS3H AC-Y1
Memory 2 x Crucial Ballistix 8GB DDR4-3000
Video Card(s) MSI Nvidia GeForce GTX 1660 Super
Storage Boot: Intel OPTANE SSD P1600X Series 118GB M.2 PCIE
Display(s) Dell P2416D (2560 x 1440)
Power Supply EVGA 500W1 (modified to have two bridge rectifiers)
Software Windows 11 Home
I got some PC2-6400 sodimms that Crucial confirms are originals, but in reality the JEDEC only goes up to PC2-5300

Crucial seems unwilling to replace them, so I am wondering if it is worth the trouble to modify the JEDEC chip using Thaiphoon burner

Any advice?
 
Does the SPD readout show up to 6400? I am asking because the ram can have multiple JEDEC profiles, but the motherboard doesn't have to pick the highest (or support it).
 
For a second I was thinking 6400 was really high. Than I remembered its DDR2 and really only 400Mhz*
 
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What´s the motherboard you installing the RAM on?

Dell Latitude E5400


Does the SPD readout show up to 6400? I am asking because the ram can have multiple JEDEC profiles, but the motherboard doesn't have to pick the highest (or support it).

The previous RAM ran at 400MHz and Speccy shows the new RAM JEDEC maxes out at 333MHz

Intreaging is this ebay auction
4GB (2x2GB) PC2-5300s DDR2-667MHz Laptop Memory SODIMM Intel 200pin | eBay
where the label is for PC2-6400, but it is being sold as PC-5300; so this might be a known issue.
 
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PC2-6400 = DDR2-800 or 400Mhz.

I would check to see what CPUz or Thaiphoon burner shows the highest JEDEC is. Does the DIMMs have a label of them?
 
Since Speccy said 333MHz and the laptop booted to 333MHz, that seems somewhat convincing (both units show a max JEDEC of 333MHz)

Crucial is giving me the run around.

PC2-6400.jpg
 
It says PC2-6400 on them, so it's really DDR2-800. But like I said, the motherboard doesn't have to support it (for whatever reason). The next step is to verify that the SPD data includes that JEDEC. If so Crucial RMA isn't going to do anything for ya. But if the SPD data only goes to DDR2-667, that would be the cause.
 
The previous RAM ran at 400MHz

Thaiphoon burner shows the maximum speed at 333MHz
 
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Weird that Crucial would sell RAM mis-branded with the wrong SPD...

I love Crucial but,
this does remind me of over-binned DDR2 dies in their early Ballistix.
(Basically, the dies all ran at 'labeled spec' but the voltage Crucial specified to get them there, was a sure-fire way to damage or kill 'em)

Betchya, those would run DDR2-800 in laptops/IndustrialPCs with BIOS options for such.
Lacking the SPD profile for it is probably more a warranty CYA than 'oversight'. That way, no one can accidentally run them "outside JEDEC spec"...
(Just like running RAM today at advertised speeds is "Over clocking" according to both Intel and AMD.)

I too, would be tempted to edit SPD.
Though, I have 0 experience with that, and generally caution such 'risky' mods.
 
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Load something, some sodimms will downclock when not used.
 
There is no 400MHz JEDEC entry

I too, would be tempted to edit SPD.
Though, I have 0 experience with that, and generally caution such 'risky' mods.

Battery just flaked out, so I am distracted by that issue; probably won't risk adding an entry to the JEDEC

Way I see it, I'm learning; so all this madness is not wasted.
 
There is no 400MHz JEDEC entry



Battery just flaked out, so I am distracted by that issue; probably won't risk adding an entry to the JEDEC

Way I see it, I'm learning; so all this madness is not wasted.
Could have sworn I had some 400mhz ddr2...............but that was a long time ago.................hmmm
actually I think I had a set of ddr2-1066 in my first phenom II board.

edit
ya think thats what i had and it ran at that no OC or xmp

edit https://www.jedec.org/document_search?search_api_views_fulltext=ddr2

SPECIALITY DDR2-1066 SDRAM​

JESD208 Nov 2007
This document defines the Specialty DDR2-1066 SDRAM specification, including features, functionalities, AC and DC characteristics, packages, and ball/signal assignments. The purpose of this Specification is to define the minimum set of requirements for JEDEC compliant 256 Mb through 4 Gb for x4, x8, and x16 Specialty DDR2-1066 SDRAM devices.
 
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The SODIMM set cost me $10 and is error free, so maybe the speed issue is just 'much ado about nothing', but next time I'll think twice before homing in on Crucial.
  • 4GB RAM $10
  • Windows 10 license $9
  • 256GB SSD $25
  • Power supply pulled from a Dell Chromebook
  • New battery $17
Not bad for a laptop in case I need one for travel.

I'm also upgrading an

HP Notebook - 15-bs020wm​

which runs Windows 11 without tricks (8GB DDR3 for this one)

Both laptops were free (beat up and filthy), so the cost is parts alone (and a lot of work).
 
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The SODIMM set cost me $10 and works, so maybe it's just 'much ado about nothing', but I'll think again before homing in on Crucial.
  • 4GB RAM $10
  • Windows 10 license $9
  • 256GB SSD $25
  • Power supply pulled from a Dell Chromebook
  • New battery $17
Not bad for a laptop in case I need one.

I'm also rebuilding an

HP Notebook - 15-bs020wm​

which runs Windows 11 without tricks.

Both laptops were abandoned (and filthy), so the cost is parts alone.
Many old intel chips capped out at 333mhz..............
you can always check your chips # on microns site..............see speed grade -187E, CL=7 = 1066 (that would be jedec)

1699408200483.png
 
Many old intel chips capped out at 333mhz..............

The original set ran at 400MHz

All these 'troubles' seem to enrich the experiance.
 
Crucial finally allowed an RMA, so I hope to have true PC2-6400 replacements soon.
 
Crucial has always granted me rma. Very good service.
 
Crucial finally allowed an RMA, so I hope to have true PC2-6400 replacements soon.
Awesome! If they approved the RMA, you should get comparable new sticks.
IIRC, (approved) RMA's (for RAM) don't get 'tested', they get 'inspected' for signs of abuse and (assuming passed inspection) replaced. AFAIK, If they cannot supply like-for-like, they'll contact you and offer closest-replacement. All of the industry has changed so-much over the years, that I wouldn't be surprised if they just replace with whatever is comparable and in-stock.
Crucial has always granted me rma. Very good service.
2nd'd.
My DDR2-800 Ballistix sets (that I burnt-thru 2 sets of back in my E6600 Vista-era build) both RMA'd w/o issue.
IIRC, it was ~1.5-2wk full turnaround time for both. Note: I lived in S. NV @ the time.
 
Crucial finally allowed an RMA, so I hope to have true PC2-6400 replacements soon.

What. ...Am surprised they accepted return of DDR2 memory. I think the problem is your laptop & those are real PC2-6400.

The problem is some laptop will default to the slower speed which is present in most DDR2," PC2-5300",.this is normal. PC-6400 profile should be present with-in the SPD, but just to insure computer starts up it defaults to PC2-5300 speed.

If you want guarantee default 6400 speed at all times, then it's best to remove or disable this speed at byte 18.



EDIT: Just to add my DIMM default to PC2-5300 even tho thay are rated @ PC2-9600
 
The original RAM runs at 400MHz and has a JEDEC entry for 400Mhz; the new RAM ran at 333MHz and did not have a JEDEC entry for 400MHz

Just got their reply:
"this is not a Crucial product and is a Samsung branded part. As such, I'm afraid we are unable to complete this RMA request"

Guess the labels were fake
 
The original RAM runs at 400MHz and has a JEDEC entry for 400Mhz; the new RAM ran at 333MHz and did not have a JEDEC entry for 400MHz

Just got their reply:
"this is not a Crucial product and is a Samsung branded part. As such, I'm afraid we are unable to complete this RMA request"

Guess the labels were fake

I did spot this, Samsung chips, but Crucial use Micron chips. So yeah, you been turned-over.
 
I think DDR2 was before Micron aquired Crucial and Crucial were using various chip vendors.

ebay refunded , so I'm only out postage to Crucial

Now to find some more RAM...
 
I think DDR2 was before Micron aquired Crucial and Crucial were using various chip vendors.

ebay refunded , so I'm only out postage to Crucial

Now to find some more RAM...

Look for Kingston PC-6400 CL4 DDR2 SODIMM. They pop up now & then on EBAYY. I have a number of them here in my collection.
 
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