How to detect if cache is real or not?

Discussion about old PC hardware.

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-10-31 @ 23:21

gerwin wrote:
Cga.8086 wrote:...there is just a few components that mine does not have and i dont know what they are for...

Is your board missing the Voltage Regulator? This item is shown in the photo below the two large red arrows. It has three legs and is also fixed with a screw. This circuit was often left out on 486s to save cost, but it means only 5 Volt CPUs are supported, no 3,3V ones, unless you add the components yourself.

BitWrangler wrote:In my experience, the UMC cache chips were usually real actually. You do seem to be missing a Keyboard Controller chip.

It was always like that, very sure nobody removed anything since the case was assembled in 1995. My keyboard works fine anyways?


In mine the voltage regulator is there but belive ir ot not it does not have the screw to make it touch the PCB :blah:
i checked the pcb to see any signs of mark to see if the screw was there but there are no markings.

mine is equal as yours, but no clue as os why there are 2 capacitors missing and a couple of orange components that i dont know what they are
If i remember correctly i tested it with a DX2 66mhz

as for the cache ... i got UMC chips, about 10, but its a pain in the ass to remove the fake cache because it is soldered directly without a socket.
so many legs, besides its difficult. if its difficult to replace a capacitor that has 2 legs, a "28pin x 9 " is hell
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby BitWrangler » 2017-11-01 @ 13:35

Nah, just get some fine point side cutters and go snip snip snip along all the pins and do them one by one.
Basement full of ancient PC stuff, starting to go through it. Most recently toyed with DOS era stuff 15 years ago, so memory might be rusty. So what's this BitWrangler guy's deal ??? >>> http://www.vogons.org/viewtopic.php?f=25&t=56382
User avatar
BitWrangler
Member
 
Posts: 383
Joined: 2017-10-11 @ 00:55

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-01 @ 13:42

that is easy, the hard part is removing the solder that is inside the holes
sometimes it is almost impossible to do 1 hole, and that has 252 holes
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby gerwin » 2017-11-01 @ 14:48

I have a manual solder pump, but when recapping that seems insufficient to clear the mounting holes in the PCB. I actually use a very small drill to clear the remaining solder from the holes. This may very well be a bad practice, but lacking any better ideas, that is what it is, and it works. The drill is equal in diameter to the leg of a Capacitor.

It is probably no longer an option for your project, but if the fake cache is internally unconnected you could have piggybacked the new cache or sockets on top of the fake cache.

Cga.8086 wrote:In mine the voltage regulator is there but belive ir ot not it does not have the screw to make it touch the PCB :blah:
i checked the pcb to see any signs of mark to see if the screw was there but there are no markings.

Strange. The screw is not essential, but I find it strange that you are missing capacitors that are part of the VRM circuit, allthough the VRM itself is there.
User avatar
gerwin
l33t
 
Posts: 2364
Joined: 2004-5-07 @ 19:21
Location: NL

Re: How to detect if cache is real or not?

Postby BitWrangler » 2017-11-01 @ 16:03

Cga.8086 wrote:that is easy, the hard part is removing the solder that is inside the holes
sometimes it is almost impossible to do 1 hole, and that has 252 holes

Sometimes I use a stainless steel sewing needle, solder doesn't stick well to it, heat it and poke it.

However, do you know a discount dollar/pound shop type place that has cheap "Vector" brand tools? They actually do a solder sucker that works pretty well, they were cheap so I bought two of them when I saw them, figuring it would break quick, but the 2nd one is still in reserve, actually lasting better than the one I got from Radio Shack for several times the price.
Basement full of ancient PC stuff, starting to go through it. Most recently toyed with DOS era stuff 15 years ago, so memory might be rusty. So what's this BitWrangler guy's deal ??? >>> http://www.vogons.org/viewtopic.php?f=25&t=56382
User avatar
BitWrangler
Member
 
Posts: 383
Joined: 2017-10-11 @ 00:55

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-01 @ 16:49

gerwin wrote:I have a manual solder pump, but when recapping that seems insufficient to clear the mounting holes in the PCB. I actually use a very small drill to clear the remaining solder from the holes. This may very well be a bad practice, but lacking any better ideas, that is what it is, and it works. The drill is equal in diameter to the leg of a Capacitor.

It is probably no longer an option for your project, but if the fake cache is internally unconnected you could have piggybacked the new cache or sockets on top of the fake cache.

Cga.8086 wrote:In mine the voltage regulator is there but belive ir ot not it does not have the screw to make it touch the PCB :blah:
i checked the pcb to see any signs of mark to see if the screw was there but there are no markings.

Strange. The screw is not essential, but I find it strange that you are missing capacitors that are part of the VRM circuit, allthough the VRM itself is there.


i see the straces on the back of the pcb, so it must be just fake cache memory.
regarding the drill...no, not good, and not good to insert the soldering iron on the hole either because you can ruin the trace.
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-01 @ 16:53

BitWrangler wrote:
Cga.8086 wrote:that is easy, the hard part is removing the solder that is inside the holes
sometimes it is almost impossible to do 1 hole, and that has 252 holes

Sometimes I use a stainless steel sewing needle, solder doesn't stick well to it, heat it and poke it.

However, do you know a discount dollar/pound shop type place that has cheap "Vector" brand tools? They actually do a solder sucker that works pretty well, they were cheap so I bought two of them when I saw them, figuring it would break quick, but the 2nd one is still in reserve, actually lasting better than the one I got from Radio Shack for several times the price.


stainess stell sewing needle is actually good.
Solder sucker i had one china branded cheap that died after few days. and it came with a fault on the cables that blew the fuses on my house.
the japanese goot ones cost like 300 dollars.

but stainless steel needle, that is actually a good idea. You heat up the solder or you heat up the needle?
then you push and should be on the other side easly.
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby gerwin » 2017-11-01 @ 23:39

Cga.8086 wrote:regarding the drill...no, not good...

Just to put it into perspective; after using the solder sucker pump there is at least dimple in the PCB hole which ensures that the drill gets centered and only drills away solder material.
User avatar
gerwin
l33t
 
Posts: 2364
Joined: 2004-5-07 @ 19:21
Location: NL

Re: How to detect if cache is real or not?

Postby aop » 2017-11-02 @ 00:09

You can clean the PCB holes with a cheapo solder sucker like this if you have three hands:
Image

I asked a friend to help with one motherboard. I clamped the board on a small bench vice and heated the PCB holes with soldering iron with small sharp bit while my friend operated the solder sucker on the other side of the board. Got all 50+ holes nice and clean.
aop
Newbie
 
Posts: 45
Joined: 2017-9-27 @ 19:17

Re: How to detect if cache is real or not?

Postby BitWrangler » 2017-11-02 @ 00:15

Cga.8086 wrote:but stainless steel needle, that is actually a good idea. You heat up the solder or you heat up the needle?
then you push and should be on the other side easly.


Bit of both I guess, hold needle in needlenose pliers or locking forceps, have iron tip kind of sideways on the hole so it touches needle, and push through and maybe go in and out a bit, scrape needle if it's got much solder on, go to next one...
Basement full of ancient PC stuff, starting to go through it. Most recently toyed with DOS era stuff 15 years ago, so memory might be rusty. So what's this BitWrangler guy's deal ??? >>> http://www.vogons.org/viewtopic.php?f=25&t=56382
User avatar
BitWrangler
Member
 
Posts: 383
Joined: 2017-10-11 @ 00:55

Re: How to detect if cache is real or not?

Postby amadeus777999 » 2017-11-02 @ 16:47

Interesting thread - I have yet to try out the manual solder sucker.
Should it prove to be inadequate I may purchase an electric one. There's one for a 100$ which looks quite professional, albeit this could be overkill in relation to how little work I'll be doing. There's a dude on youtube who is repairing ZXs aplenty, with lots of de/soldering action, and even he's getting by with a manual solder pump.
User avatar
amadeus777999
Member
 
Posts: 180
Joined: 2013-7-04 @ 17:04

Re: How to detect if cache is real or not?

Postby bjwil1991 » 2017-11-02 @ 16:53

I bought myself a 45W Desoldering Iron and No-clean electronic solder flux at a computer store I always go to, and 5 packs of Solder Braids from eBay. I've desoldered my Aztech Sound Galaxy NX Pro to do proper soldering for the jacks and volume potentiometer since the previous job I did was only with a soldering iron, and an nVidia Riva TNT2 M64's VGA connector as well since it was on its last legs.
C64, WheelWriter 10 Series II, Pack-Mate 28 Plus, K6-2/300, Pavilion N3350, iMac G3/600 Graphite, Socket 370, Pavilion 7955, Athlon 64, Dimension 4550, Dimension E510, ThinkPad R40, Presario C700, ASUS X54C, Raspberry Pi B+, 2-3, Custom FX-6300
User avatar
bjwil1991
Oldbie
 
Posts: 551
Joined: 2013-8-14 @ 03:10
Location: United States of America

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-02 @ 19:14

aop wrote:You can clean the PCB holes with a cheapo solder sucker like this if you have three hands:
Image

I asked a friend to help with one motherboard. I clamped the board on a small bench vice and heated the PCB holes with soldering iron with small sharp bit while my friend operated the solder sucker on the other side of the board. Got all 50+ holes nice and clean.


that thing does NOT work
it might work on some , but specially on ground points its impossible, even leaving the iron to make it melt it sucks just a little bit on GROUND points.
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby GPA » 2017-11-03 @ 13:46

works better with a heat gun )
GPA
Newbie
 
Posts: 95
Joined: 2016-6-26 @ 15:28
Location: UK

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-03 @ 14:58

GPA wrote:works better with a heat gun )



heat gun? or heatgun + solder sucker from the other side of the board?
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby gdjacobs » 2017-11-03 @ 21:19

With a heat gun, you can desolder all SMT components on one side of the board.
User avatar
gdjacobs
l33t
 
Posts: 4178
Joined: 2015-11-03 @ 05:51
Location: The Great White North

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-08 @ 19:14

Watch this awful job

the most time demanding job , i have been working for hours...

-Cutting the legs of the fake cache,
-removing with solder the leftoff of the leg in the hole.
.Using desoldering braid to clean the remainings in the hole

and still need to work on more holes.

I can only say one thing.......Desoldering Braid + flux, is the miracle of his century. I can´t belive, i never used braid and gave it a try, i was shocked to see how good it works for sucking that solder from the holes and leving the hole empty. I cant belive i never used this when i replaced capacitors from motherboards, and i struggled with a needle to make the hole open

Image
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby amadeus777999 » 2017-11-08 @ 23:35

Well done.
Sucks, that not both banks support 32pin chips... although 256KB cache in total is mostly sufficient.
User avatar
amadeus777999
Member
 
Posts: 180
Joined: 2013-7-04 @ 17:04

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-10 @ 04:30

i finished
it is good to do it once, and never again. what a pain in the ass

the quality of this motherboard is really good, better than the pcchips bending ones.
it always boots on first try.

Image

Image

i would never do this job again
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

Re: How to detect if cache is real or not?

Postby Cga.8086 » 2017-11-10 @ 13:05

the only thing i did not like was the 8 KB L1 cache.
is that upgradable to 16 KB L1 cache ?, don´t even know where that L1 cache is on the motherboard.

I also installed 32mb of memory. its more than enough for windows95 and about the recommended per microsoft for windows98
Cga.8086
Newbie
 
Posts: 67
Joined: 2017-4-16 @ 22:38

PreviousNext

Return to General Old Hardware

Who is online

Users browsing this forum: Google [Bot], LHN91 and 11 guests