A7N8X-VM/400 random reboots

[Driekes]

I keep holding problems with the A7N8X-VM/400 boards. I get random reboots
all the time. First I thought that the Sempron 2400+ cpu wasn't supported.
So I installed a Athlon XP 2700+ but still no solution. Bios 1003 is
installed (fried one board after upgrading to the latest beta bios version)

This is what I tried:

- Changed mainboard (brand new one)
- changed power supply
- changed harddisk / memory (Kingston KVR333 512Mb), really everything and
reïnstalled Windows XP Prof sp1 for several times.

I build many Sempron 2400+ / A7V400-MX (less expensive!)systems without any
problem at all.

Does anyone has the Sempron/Athlon XP - A7N8X-VM/400 combination work for
100% ?

Thanks!

Werner

 

[Paul]

I keep holding problems with the A7N8X-VM/400 boards. I get random reboots
all the time. First I thought that the Sempron 2400+ cpu wasn't supported.
So I installed a Athlon XP 2700+ but still no solution. Bios 1003 is
installed (fried one board after upgrading to the latest beta bios version)

This is what I tried:

- Changed mainboard (brand new one)
- changed power supply
- changed harddisk / memory (Kingston KVR333 512Mb), really everything and
reïnstalled Windows XP Prof sp1 for several times.

I build many Sempron 2400+ / A7V400-MX (less expensive!)systems without any
problem at all.

Does anyone has the Sempron/Athlon XP - A7N8X-VM/400 combination work for
100% ?

Thanks!

Werner

Like many users of Nforce2 chipsets, you'll need to experiment with
RAM, until you find some that works well for you.

If I go here, and search for the two terms "picky" and "ram", I get
323 hits (click the "Search for all terms" button). Maybe you'll find
some info on nforcershq, to help narrow the search for RAM that works.

http://www.nforcershq.com/forum/search.php
http://www.nforcershq.com/forum/search.php?mode=results&sid=29de7e1ce274c19a7c3df9bd20e0a899

You need to test the memory, both with memtest86 (from memtest.org)
and Prime95 torture test (mersenne.org). I had some ram that passed
memtest86 but failed Prime95 in about half an hour. Don't ship a system
till it passes Prime!

HTH,
Paul

 

[Driekes]

Okay, thank you Paul, I saw many post from you before, your the real expert!
! I will do some tests with the memory. It's a strange board(or chipset)...
For my own system I use a A7N8X-X (normally with XP 2700+ but now with
Sempron 2400+) with the same ram (Kingston KVR400....) and it's running for
almost a year without a problem. I builded a like a dozen of systems with
this board and never saw them back again. So could you say it's the nForce2
IGP that is giving problems?

Werner pa5rsw

 

[Paul]

Okay, thank you Paul, I saw many post from you before, your the real expert!
! I will do some tests with the memory. It's a strange board(or chipset)...
For my own system I use a A7N8X-X (normally with XP 2700+ but now with
Sempron 2400+) with the same ram (Kingston KVR400....) and it's running for
almost a year without a problem. I builded a like a dozen of systems with
this board and never saw them back again. So could you say it's the nForce2
IGP that is giving problems?

Werner pa5rsw

<<snip>>

In the case of the A7N8X-VM, the Northbridge appears to be the limiting
factor. When chips have a lot of I/O pins on them, there can be noise
issues when all the I/O's are switching at the same time. In any silicon
technology, there are design rules to prevent this - each set of I/O
pins is supposed to have its own power/gnd supply. By keeping a certain
ratio of power/gnd pins to I/O pins, a chip can be kept stable.
Violating the rules leads to the issues you see with IGP. The fix for
this at the chip design level, is to use an IC package with more
electrical connections on the bottom of the chip, but that makes the
chip more expensive.

As I've been experimenting with only one AMD motherboard, that
hardly makes me an expert. I'm surprised how hard it is to find
RAM to make these boards work well, and from a electrical design
point of view, it shouldn't be this tough. In your case, with
the A7N8X-VM/400, what you could try, is either expensive RAM and
no AGP video card, or try cheap RAM and use a FX5200 video card
on each system. You may find that by disabling the video logic
circuitry in the Northbridge, when the FX5200 is plugged in,
is enough to keep the system stable. (Disabling video logic
reduces chip core electrical noise, and could reduce power
consumption on the Northbridge by a couple watts.)

HTH,
Paul

 

[Rob Stow]

Okay, thank you Paul, I saw many post from you before, your the real expert!
! I will do some tests with the memory. It's a strange board(or chipset)...
For my own system I use a A7N8X-X (normally with XP 2700+ but now with
Sempron 2400+) with the same ram (Kingston KVR400....) and it's running for
almost a year without a problem. I builded a like a dozen of systems with
this board and never saw them back again. So could you say it's the nForce2
IGP that is giving problems?

I have built several systems - somewhere between 25
and 30 - with the A7N8X-VM/400 and no problems yet
regardless of whether the system is using the IGP or
whether a card has been stuck in the AGP slot.

I never use flaky RAM like the stuff from Kingston or
PNY. I usually use matched pairs of Mushkin or Corsair
DIMMs and run them at their rated specs, but a few times
I have also successfully used a pair of plain-vanilla
Samsung or Crucial PC3200 DIMMs.