Thinkpads Forum

I bought an X61 on eBay quite some time ago. I only got it out of the cupboard recently however and today I discovered that the CPU is an ULV "L7500" (according to /proc/cpuinfo). "dmidecode" on Linux reports that I have an "X61s" (model number "7667A11"). Were X61s motherboards ever sold in a chassis marked "X61"? Or did someone replace the motherboard before I bought the computer? I was about to purchase a new fan and heatsink assembly. Lucky I noticed as the assemblies are not compatible between 's' and non-'s' models.

The laptop runs quite cool compared to my old X61 (even despite the anaemic fan currently installed). I thought this was just due to the SSD upgrade but it looks like I might have the unexpected ULV CPU to thank.

I'm not sure if an X61s motherboard can be (easily) swapped into an X61 chassis. Looking at my own X61 and X61s, it appears that all of the mounting screws are in the same place and port locations identical between the two. The only visible difference is in the battery bay; the "s" is a little wider - 176mm vs. 161mm.

Assuming it is possible, and that the programs you are using to read the model type and CPU information off the motherboard are accurate, then, yes, it could be that somebody replaced the motherboard before you got it. I wouldn't think that the factory would install an "s" motherboard and leave the badging as a "non-s" model.

However, another possibility exists. It could be that somebody replaced the "clear plate". That is the strip of plastic below the bottom of the screen containing the printed model type and the LED status icons. As a check, what does the model type label on the bottom of the system say? If it matches the 7667-A11 AND the battery bay is 176mm wide, then I'd say somebody replaced the plate. If, on the other hand, the model type matches one for an X61 system AND the battery bay is only 161mm wide, then somebody changed the motherboard.

It's trivially easy to put an X61s board in an X61 chassis, because the boards are exactly the same size and the screw holes line up perfectly.

The reverse has already been done: someone in this forum put an X61 board in an X61s chassis. IIRC he used the X61s heatsink, which IMO is not really adequate for the job.

The X61s runs a lot cooler due to the Low Voltage processor: 17 watts TDP and 27 watts max power consumption. Contrast this to a Normal Voltage processor on the regular X61: 35w TDP and 53 watts max).

Here are two pics that will help you differentiate the X61 and X61s:

http://thinkwiki.de/Datei:Vergleich_X6x_X6xs_1.jpg
The X61 is on top, and the X61s at the bottom.


http://thinkwiki.de/Datei:Vergleich_X6x_X6xs_2.jpg
The X61 is on the left, X61s is on the right.


You should compare the Machine Type written on the label on the underside of the laptop with the info you got from software.
If they match, then it's possible that the entire lid was replaced. If they're different, then the board was replaced.

You got lucky!

I put x61s motherboards into x61 bases to help make the machine cooler and use the x61 fan. There is a little more air inside the x61 base, and the x61 fan/heatsink is more capable of cooling, even if it isn't spinning.

Thank you all for your assistance. After examining my laptop it turns out the situation is as rkawakami suggested; it is an X61s with only the "clear plate" replaced. This is less interesting than some sort of hybrid, but still interesting (to me at least) nonetheless. Who replaced the clear plate before I acquired the machine? And for what reason? I will never know.

jaspen-meyer wrote:You got lucky!

I put x61s motherboards into x61 bases to help make the machine cooler and use the x61 fan. There is a little more air inside the x61 base, and the x61 fan/heatsink is more capable of cooling, even if it isn't spinning.

It's good to know that this is a possibility; I might give it a go in the future.

OhneHerren wrote:Who replaced the clear plate before I acquired the machine? And for what reason? I will never know.

It's possible that the entire lid assembly was replaced, perhaps due to some physical damage, or to change the LCD panel. The lid assemblies of the X61 and X61s (as well as the X60 and X60s) are interchangeable.

Does the new clear plate include bluetooth or wwan windows? The previous owner may have added these features and replaced the clear plate so the LEDs would be visible.

Well, I'm also having the almost exact same thing.

X61 chassis (excellent quality, by the way) with a X61t (yes, tablet) mobo inside. I have checked the codes at Lenovo's site and it is indeed an X61tf strang frankenpad. Also, the display is seemingly from an X60(s) machine, as it's N121X5, according to ThinkWiki. (used get-edid | edid-decode for this)

Not that I have any complaints.. overall an excellent machine. But if anyone from the future reads this, X61t fits inside X61.