I have two problems here: 1. One of the two modules evidently doesn't work. 2. I am not sure either is really PC2-6400 I bought a couple of DDR2 4GB memory modules on Ebay the other day and I just received them: 4-GB-X-2-8Gb-DDR2-800-200-Pin-PC2-6400-Unbuffered-SODIMM-x64-U-S-A I put them in my Lenovo T61 today and found that evidently only one of them works. You see two modules in the linked ebay listing photo. The laptop only starts if the bottom module is in the first slot. Otherwise I get 4 beeps. If I have just the bottom one installed (in slot one in the laptop), it starts. If both are installed and the bottom module in the listing photo is in slot one, it starts OK too (Windows 10), but either way the System About screen shows only 4GB memory installed. I figure the top shown module in the listing photo is bad. I'm running memtest86 version 4.00 on the working module: https://photos.google.com/photo/AF1QipO51jOkQ-R2MLncSyDFaPfLB3xv01sNERHFfqLX I'm kind of thinking that this isn't PC2-6400 but is actually PC2-5300, am I right about that?
That's really not the question: Is this PC2-6400? Yes, my T61 is speced at 5300 but will work with 6400. In my position, it not being as specified in the listing is further argument that I'm entitled to a refund, that is all. Worse, of course, is that one of the modules doesn't work. This may be because it was damaged in shipping. The seller wrapped the modules together in a small piece of small bubble bubble-wrap and shoved that in a typical small yellow shipping envelope. I think that's risky. It may have worked when they sent it, it did not when received. :'( I will pack the modules more securely for their return trip. Perhaps the seller can redeem their investment by pursuing the lifetime warranty shown in the listing from Axiom.
Run CPU-Z with the working stick installed and check the SPD tab, that will answer your question. http://www.cpuid.com/softwares/cpu-z.html
The Ebay link you provided shows it is model AX2800S5Y/4G which is PC2-6400. The sticks should have the model number on them. If your system can only go up PC2-5300, that's what it would show (I can't see whatever attachment you had for some reason). Maybe the system will only work with one due to your system limitations. Try each one individually, and see if your system works. If it does, then you have your answer.
memtest86 shows this when running the sole working stick: [/IMG] The sticks look like this: [/IMG] The stick that doesn't work didn't work in either slot, the other being empty. It's PC2-5300. My machine will work with PC2-6400, I have it on good authority. There is nothing on the sticks to indicate that they are actually AX2800S5Y/4G.
Well, if one of the sticks won't work even when it's by itself, then it must be defective. However, I looked at your Lenovo T61 specs, and from their tech specifications, it says that it only works with ram speeds up to 667 Mhz (or PC2-5300). Faster sticks may work fine in in, but your speed will be capped at 667 Mhz. And if you double the 332 Mhz (since it's DDR) you get to the 667 Mhz you are capped at. But maybe you have seen something I am not seeing about the Lenovo using faster ram than the Lenovo specs show. https://support.lenovo.com/us/en/documents/pd012623 https://forums.lenovo.com/t5/ThinkPad-T61-and-prior-T-series/RAM-speed-T61p/m-p/642189#M60213 You can always use a utility to tell you more info about the ram like this one: http://www.passmark.com/products/rammon.htm
GM965 doesn't support 8GB memory only up to 4GB. Mobile 965 Express Chipset (Family) Datasheet: http://www.intel.com/Assets/PDF/datasheet/316273.pdf
I'm told that Lenovo didn't officially support 8GB for the T61, I think because they didn't have time to test it, however it does work. The spec on the machine is PC2-5300, however some people are using PC2-6400. Presumably there's no advantage in doing so, however it was suggested to me in this thread that it's fine to get the faster sticks: Win7--->Win10 evidently solved a bad problem with T60 In that thread it is stated: "Yes, as far as I can tell all T61s (Merom and Penryn) can take 8GB of RAM as the Intel 965GM/965PM can take up to 2 sticks of 4GB (I run both my main T61s on 8GB PC2-6400 RAM"
The BIOS, Windows, or SPD readers may be 'reporting' 8GB but it's likely not actually using any of it over 4GB. Otherwise, it's an unsupported configuration by Intel (i.e. unsupported mod). The PC2-6400 shouldn't matter the one stick is most likely defective.
From thread: Win7--->Win10 evidently solved a bad problem with T60: "I don't know where you're going with this. In a 64-bit environment, *61-series (excluding "Z" units) can most certainly use 8GB of RAM. When Intel first announced this chipset, 2GB was the largest single DIMM produced and that's where the 4GB limit cited by both Intel and Lenovo comes from. It's really *that* simple." In that thread it's also suggested that PC2-6400 is recommended for the T61 even though the bus speed will be limited to the same 667Mhz as PC2-5300 because the former run cooler, and can often be found cheaper to boot.
I just received my 2 4GB sticks of Elpida PC2-6400 and swapped out my 2GB sticks and now the machine reports 8GB. No surprise there. I think the thing to do is run memtest86 to make sure I don't get any errors. I suppose a single pass is sufficient.
Yeah I was confusing 965 series with 945 era chipset memory limits. Been too long since then with too many chipsets to keep in the noggen.
