GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

[pfrcom]

I was given this GA-6VEM a couple of years ago
Using VIA's PLE133T chipset, it supports Tualatins - so I replaced all bulging caps, retaining the 330uf 25v Choyos

[pfrcom]

Re: GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

Fitted with a Tualatin 1400-S, it was quite a snug fit in a well made IBM Aptiva case, to make a respectable performance computer
Now, a couple of years later, I decided to use that computer to play with Linux
Fired it up, to be greeted with "Keyboard error or no keyboard detected"
Tried many keyboards, and only one worked - an old HP where the numeric keypad doesn't work
By this time I'd convinced myself it must be the original Choyo caps causing the problem, so I replaced them with 1000uf 6.3v Suncon

[pfrcom]

Re: GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

Made no difference - so I tried removing the battery to force a CMOS reset
Only result was now I had the classic "Keyboard error - Press F1 to continue"
After using the HP keyboard to set it up, I thought "Compatibility - maybe a firmware issue"
So I reflashed to second last BIOS F7 instead of latest F8, without any improvement - same for original F4 BIOS
By this time I was thinking of what I could use in the Aptiva case - not a lot of choice, given the snug fit
I couldn't face shoehorning in something else where it's not meant to go, so I thought of the Asus problem from this posting
https://www.badcaps.net/forum/showpo...7&postcount=10
The GA-6VEM did have a similar looking component, but C181 instead of Asus's C151 - shown in this pic at CP3, sandwiched between the keyboard fuse and the PS/2 connector block

[pfrcom]

Re: GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

What the hell ? - I attacked it with a soldering iron, removed C181, leaving the board like this

[pfrcom]

Re: GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

To give a perspective, here's the removed C181, sitting on one of the Suncon caps

[pfrcom]

Re: GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

Now the acid test - was I going to get the magic smoke, or what ?
Hooked it all up for the umpteenth time, powered on, and success
Now it's back in the Aptiva case, and has successfully worked through some installs of XP and Linux

[cufarmer]

Re: GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

Congratulation. Good pics.

[larrymoencurly]

Re: GA-6VEM PS/2 ports fixed - it's not always bad electrolytics

What's the purpose of those C181 and C151 capacitor packs, to ground noise or spikes from the I/O lines?