[HowTo] Upgrading RAM to 128 MB (WL-500gP, WL-500W and WL-700gE)

[Pim Borst]

I have been searching for a memory module too and found out that the chips on the Kingston KVR333X64SC25/512 that is listed in this thread are not usable. They are 32M x 8-bit (8M x 8-bit x 4 Bank) DDR333 SDRAM sealed in uBGA packages. See http://www.valueram.com/datasheets/K...64SC25_512.pdf.

Maybe they used to have the right chips and Kingston changed them...

Better check the datasheets before you buy one.
The Transcend module seems OK: http://www.transcendusa.com/Support/...3M_1184_s1.pdf

[wpte]

well... still it's 64MB
or I should say this: because the processor is 32bit, it will be able to adress only 32bit of the 64bit lane on the RAM module, so you get double space and it becomes 128MB

but that seems to be really theoretical

[Pim Borst]

I just received the Transcend module.
It has Hynix chips nowadays so if you are looking for Samsung or Elpida chips don't buy this module.

If you do buy this module, you can 'harvest' the 22ohm resistors from R1-R8 from the chip-side of the module or R9-R16 from the back-side. To get the clock timings right I will try to transplant one of the capacitors C26-C29 from the back-side the way NotebookKiller suggested.

To Wpte: each chip has 32M addresses storing 16bits (2 bytes, one word) of data each. That makes 2Bx32M=64MB per chip so the two chips will get you 128MB. For reading/writing a single byte the chips have UDQS and LDQS pins to activate the upper or lower byte only. See the datasheet http://www.hynix.com/datasheet/pdf/d...TP(Rev0.3).pdf

[andrewr]

To Pim Borst:

Do you know which lines the capacitor should be soldered? It isn't very clear on the photo attached in NotebookKiller's post. There are two lines that are very close to each other.

[Pim Borst]

Hi Andrew,

The two lines that are close to each other are the clock lines indeed.
I removed some of the PCB mask and measured that they are connected to CK and /CK of the chips (see the datasheet in earlier post).

Wednesday a colleague of mine is going to help me with the upgrade. He has professional hot-air soldering equipment. I hope it will work. Good luck with your WL500, I hope you get it working again!

To Pim Borst:

Do you know which lines the capacitor should be soldered? It isn't very clear on the photo attached in NotebookKiller's post. There are two lines that are very close to each other.

[tcharron]

I tried to upgrade my wl500gp v1 to 128m using this guide.

I salvaged some chips from an SDRAM board (Nanya 32x16).

I installed U3 successfully and ran memtest against it overnight with no errors.

I installed U4, and after some solder touchups it booted fine. I configured the settings for 128m and rebooted and it came up. Memtest ran up to test 14 and then reported an error. It had a total of 3 errors after the first iteration.

I shut it down to touch up my joints and haven't been able to get it boot since. I can only assume that bad joints are causing the problem. I will get some flux and have another go at it (I installed without the use of flux the first time). Any other tips?

[tcharron]

An update...

I picked up some solder paste. I was surprised that the local shop here (Active Surplus in Toronto) didn't have plain flux, but I think that the paste worked better for me.

Without removing the chips, I smeared some paste on the U4 contacts and just heated each solder joint. This worked well -- I could hear the flux burning off and could see the solder flowing into the joints. Under magnification, the joints looked a lot better after this process

Of course, it still didn't boot. SO, despite my certainty that U3 was working well (see my prior post) I gave the same treatment to U3 and lo and behold everything worked after that. I used SCP to get memtest onto the router (this was far easier than configuring the router connected to the internet) and will run memtest next.

So, a $3 tin of solder paste was the solution and I have about $2.99 of it left to spare. Cool!