wrong memory!! for sure !
for get the fan, its just protecting system with dead BIOS
dead ram ,kills everything but the power chip (brain)
getting the correct memory is NON TRIVIAL!
the correct memory must match what the processor needs.
if and intel process , it has a memory controller, MMC
that has very strict rules on memory "topology" and max.
in some cases , if you buy the memory off of the site
called Kingston you will get the correct memory.! (direct)
may sites that sell memory (non pro) have a ton of lies there.
they are ignorant of facts.
watch out for scalpers.
The memories called out by HP are not sold now.
so we use the Intel rules, (only) to pick the correct DRAM .
even one year,older processor may need older style memory.
Your PC has a full name, not shown by you.
the suffix letters, in said pn tell what the PC came with.
including all processors used, (vast) intel and AMD.
here is 1 example.(its not yours, its just a random tag)
see that 1250us there, its very important that.
here is what must match:
pin count on DMM sticks 184 , bingo easy, peasy.
voltage. some run dual voltage others do not. (no PC stated so..)
the Best memory is low voltage but work so both,1.35 and 1.5v.
(a tad slower on 1.5v) <<< sorry that is tricky too...
number of DRAM per Stick
the chips, many be limited to max size per chip, (called density)
and number DRAM per of side. some are 1side other 2 side.
and DRAM internal topology (no PC stated or exact processor so..)
speed must be equal or better
best is a matching pair,
the process or has max memory size per socket too....
here is my i5
end the end, the RAM must make the processor memory manager happy,, must
so why not post your device tag so we can stop guessing
rule 1: if BIOS cant see your sticks correctly and size
all is LOST. did you look there, no, BIOS is dead.
Best , is to let Kingston fit you out,and not worry topology.
here is the Intel page.
example , not YOURS.
shows how fussy the i5 is. early k7's same fussy but different
some processors are 1.3v only others 1.5v and some are dual.
you cant guess this, you just look it up, for your unstated processor
on old system buying new memory
you find the chip density TODAY way larger, and the old processor
can not run those either...
I looked at your PC, some are AMD
and some are with nforce chip sets.
the service tag tells us (whats in that case and mother board)
and guess what, both those , have there own rules on memory
my last question is why spend hard money on this old dog
why not retire it.
why not get a newer system. ? even a DT, box e-machine.
like here
https://www.walmart.com/search/?query=deck%20top%20computers%20on%20sale
the HP A1400 series is no longer supported by HP
why not find a newer DT and invest in it? not try to keep this old slow PC working,,,
http://support.hp.com/us-en/retired-products
http://support.hp.com/doc-images/348/c03330616.jpg