Memory upgrade for an MSI Wind U135

I own an inexpensive netbook that I take with me when I travel. Specifically, an MSI Wind U135. It’s been serving me well for almost 5 years, and the other day I decided to upgrade it a bit, by adding some memory.

After some online research, it was clear I could only upgrade from the builtin 1GB to a total of 2GB, adding a 1GB memory module. What was not so clear though is what specific model of memory I needed. This netbook uses DDR3 SDRAM, but it’s not as easy as just buying that:

On the BIOS setup menu, it lists the “System Bus Speed” as 667MHz. The tool dmidecode confirms this, but doesn’t add anything to it1:

 1$ sudo dmidecode --type memory
 2# dmidecode 2.12
 3SMBIOS 2.6 present.
 5Handle 0x0029, DMI type 16, 15 bytes
 6Physical Memory Array
 7        Location: System Board Or Motherboard
 8        Use: System Memory
 9        Error Correction Type: None
10        Maximum Capacity: 4 GB
11        Error Information Handle: Not Provided
12        Number Of Devices: 2
14Handle 0x002B, DMI type 17, 28 bytes
15Memory Device
16        Array Handle: 0x0029
17        Error Information Handle: Not Provided
18        Total Width: 64 bits
19        Data Width: 64 bits
20        Size: 1024 MB
21        Form Factor: DIMM
22        Set: None
23        Locator: A1_DIMM0
24        Bank Locator: A1_BANK0
25        Type: <OUT OF SPEC>
26        Type Detail: Synchronous
27        Speed: 667 MHz
28        Manufacturer: A1_Manufacturer0
29        Serial Number: A1_SerNum0
30        Asset Tag: A1_AssetTagNum0
31        Part Number: Array1_PartNumber0
32        Rank: Unknown

This would narrow down the search to one of the following models listed on Wikipedia (only relevant extract of the table shown):

JEDEC standard modules (extract)
Standard name I/O bus clock Module name Timings
666.67 MHz PC3-10600 7-7-7

At this point, I had no idea of whether any of the listed 4 types was ok or I should find out which exact one I needed. I know next to nothing about hardware, and I wasn’t going to risk it. I needed more information.

I opened up the netbook and looked inside. The builtin memory module is easy to find: four black rectangles lined up in front of the empty upgrade slot:

The memory module, built into the motherboard

The memory module, built into the motherboard

Each one of the black rectangles has an inscription with details about the manufacturer, as well as the part model and number. It’s tiny and difficult to read. A picture can help to make out the text. In my case, they look like this:

A single memory chip, inscribed with model parts and numbers

A single memory chip, inscribed with model parts and numbers

That’s a mouthful, but it makes for a starting point. I decided to look up “H5TQ1G83BFR” first. I got a few links as a result, but the one that was most interesting was a PDF with technical details of the products offered by the manufacturer. The first page lists three product lines, one of which is “H5TQ1G83BFR-xxC”, where the “xxC” part would match up the inscription “H9C” on my chips. Promising!

As mentioned, I know nothing about this topic, so the document could be in Klingon for all I can understand. Thankfully, I just needed part numbers. Since the document seems to cover the “xxC” lines, and I own an “H9C”, I looked up “H9”, and found exactly what I wanted (again, an extract for the relevant table):

Operating Frequency (extract)
Speed Grade (Marking) Remark (CL-tRCD-tRP)
-G7 DDR3-1066 7-7-7
-H9 DDR3-1333 9-9-9

According to this, my netbook uses DDR3-1333 9-9-9 which in turn, according to Wikipedia, means the exact spec is DDR3-1333H. With that information (and remembering I was limited to buying 1GB of memory), I could finally go online shopping with enough confidence that I was getting the right product.

  1. Info on using dmidecode at HowtoForge