503+ jumper help! (puzzle)

OK, I can think of several things to try. First, set the motherboard to
run at 2x66 @ 2.4V. AMD K6-x processors interpret a 2x multiplier at 6x,
so you will really be running at 6x66 = 400 MHz. Since you have a
heatsink/fan from an Athlon XP 2500+, heat from the higher voltage will
not be a concern in the short term.

2x/6x multiplier:
FREQ1=2-3
FREQ2=1-2
FREQ3=1-2

66 MHz FSB:
CLK1=1-2
CLK2=1-2
CLK3=1-2
CLK4=2-3

66 MHz SDRAM:
SDRAM1=1-2
SDRAM2=2-3
SDRAM3=2-3

2.4 V:
VR 3-4


If this works, then try the "regular" settings for a K6-2 400 (4x100),
but with 2.4 V instead of 2.2 V. This will test whether your RAM will
work at 100 MHz or not.

4x multiplier:
FREQ1=2-3
FREQ2=1-2
FREQ3=2-3

100 MHz FSB:
CLK1=1-2
CLK2=1-2
CLK3=2-3
CLK4=1-2

100 MHz SDRAM:
SDRAM1=2-3
SDRAM2=1-2
SDRAM3=2-3

2.4 V:
VR 3-4


If the memory works at 100 MHz, try increasing the multiplier to 4.5:

FREQ1=2-3
FREQ2=2-3
FREQ3=2-3


If the memory does not work at 100 MHz, there are two possibilities. One
is to run the FSB at 100 MHz and the RAM asynchronously at 66 MHz. I
know the manual says not to do this, but I have done it myself and it
works fine.

100 MHz FSB:
CLK1=1-2
CLK1=1-2
CLK1=2-3
CLK1=1-2

66 MHz RAM:
SDRAM1=1-2
SDRAM2=2-3
SDRAM3=2-3


Another possibility is to run both the FSB and RAM at 75 MHz, with a CPU
multiplier of 2x/6x:

2x/6x multiplier:
FREQ1=2-3
FREQ2=1-2
FREQ3=1-2

75 MHz FSB:
CLK1=1-2
CLK2=2-3
CLK3=1-2
CLK4=1-2

75 MHz SDRAM:
SDRAM1=2-3
SDRAM2=2-3
SDRAM3=2-3


There is also the possibility that your motherboard may just not support
the K6-2 450, if it does not have the "EO037" sticker. If that is the
case, you may have to make do with however fast you can manage to make
the CPU run.

Finally, once you have figured out how to get the CPU to run, try
lowering the voltage back down to 2.2 V. If the computer does not boot
or is not stable, then chances are you probably have a 2.4 V part:

2.2 V:
VR 5-6


Hope this helps.

--Alex



Aron Hubbard wrote:

 > Hello,
 > I bought my 503+ in 1998. My manual is for version 1.1 of the
 > board and I have version 1.2A. After a few years I upgraded and gave
 > this computer to my grandmother. Now she's upgraded and I have it
 > back. It had a k6/2-333 in it, but I found a k6/2-450 to use. I can
 > not get it to boot with the 450!
 >
 > Here's the original jumper settings:
 > CLK1: 1-2
 > CLK2: 1-2
 > CLK3: 1-2
 > CLK4: 2-3
 >
 > FREQ1: 1-2
 > FREQ2: 2-3
 > FREQ3: 2-3
 >
 > SDRAM1: 2-3
 > SDRAM2: 2-3
 > SDRAM3: 2-3
 >
 > So I guess I have 66mhz RAM in there. I understand there's two
 > k6/2-450's versions(?) BUT I only had the 333 heatsink. I had an old
 > 2500+ heatsink laying around, so I used that for the 450. It was
 > EXTREMELY difficult to get on, and I'm afraid I can't get off now
 > without damaging the board, so I can't read which version it is.
 >
 > I went to <a style='text-decoration: underline;' href="http://home.t-online.de/home/kai_kramer/503+.html" target="_blank">http://home.t-online.de/home/kai_kramer/503+.html</a> and found
 > the jumper settings there, but I'm afraid I don't understand the
 > RAM-Speed and Divisor setting. It lists:
 >
 > RAM SPEED: AGP = SDRAM1 1-2 and CLK4 2-3 OR
 > CEF = SDRAM1 2-3 and CLK4 1-2 (no other options)
 >
 > However my original settings setup was 2-3 and 2-3.(??)
 >
 > Can anyone make sense of this mess?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 503+ jumper help! (puzzle) 

could be it needs 2.4v, check those jumpers. also I have noticed
some motherboards don't change easily, esp fsb. once ran for a while at
one bus its hard to get them to switch to another. have seen this. very
odd, mostly older boards, but newer ones have done the same thing. I
wouldn't have put the 2500+ hsf on there, not necessary, but its on
there now ! actually I have a 333 and runs like a champ in a DFI board
that is very similar to the 503+. I am sure you can get the 450 running.
what ram is installed ?

Aron Hubbard wrote:

 >Hello,
 > I bought my 503+ in 1998. My manual is for version 1.1 of the
 >board and I have version 1.2A. After a few years I upgraded and gave
 >this computer to my grandmother. Now she's upgraded and I have it
 >back. It had a k6/2-333 in it, but I found a k6/2-450 to use. I can
 >not get it to boot with the 450!
 >
 >Here's the original jumper settings:
 >CLK1: 1-2
 >CLK2: 1-2
 >CLK3: 1-2
 >CLK4: 2-3
 >
 >FREQ1: 1-2
 >FREQ2: 2-3
 >FREQ3: 2-3
 >
 >SDRAM1: 2-3
 >SDRAM2: 2-3
 >SDRAM3: 2-3
 >
 >So I guess I have 66mhz RAM in there. I understand there's two
 >k6/2-450's versions(?) BUT I only had the 333 heatsink. I had an old
 >2500+ heatsink laying around, so I used that for the 450. It was
 >EXTREMELY difficult to get on, and I'm afraid I can't get off now
 >without damaging the board, so I can't read which version it is.
 >
 >I went to <a style='text-decoration: underline;' href="http://home.t-online.de/home/kai_kramer/503+.html" target="_blank">http://home.t-online.de/home/kai_kramer/503+.html</a> and found
 >the jumper settings there, but I'm afraid I don't understand the
 >RAM-Speed and Divisor setting. It lists:
 >
 >RAM SPEED: AGP = SDRAM1 1-2 and CLK4 2-3 OR
 > CEF = SDRAM1 2-3 and CLK4 1-2 (no other options)
 >
 >However my original settings setup was 2-3 and 2-3.(??)
 >
 >Can anyone make sense of this mess?
 >
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 503+ jumper help! (puzzle)