I’ve written a number of entries about my attempt earlier this year to update my older PC with a new motherboard and an Athlon 2600+ processor (this, this, this, this, this and this). I didn’t really isolate the problem although I’ve been using the PC for the last half year without any major problems with the exception, that the Internet Explorer keeps dying. My son plays his computer games without noticing any real problems.
Now, while going through the clutter on my desk, I came across a special diagnostic CD, which came with issue 11/2005 of the computer magazine C’t from the Heise publishing house. So, I decided to give the CD a try to see, if it included a tool, which might help me to pinpoint my particular problem. To my happy surprise, one of the included tools indeed showed a problem.
The tools, which produced a positive result (an error in my case) is Hardalyzer. Here is an extract from the system information view (output is in German, but pretty self explaining):
Hersteller: AMD
Typ: Athlon XP / MP / Mobile XP
Kern: Thoroughbred
Bek. Takte: 1666..2167 MHz FSB: 133..166 MHz DDR
Eigenname: AMD Athlon(tm) XP 2600+
Gemessen: 2079.5 MHz (12.50x 166.4 MHz)
Rating: zw. 2400+ u.2600+ (bei gemess.Takt)
Befehlssätze: FPU,Ext.MMX,Ext.3DNow!,SSE
L1-Cache: 64K+64K
L2-Cache: 256K unified
---------------------------Board & BIOS----------------------------
BIOS-Hersteller: Phoenix-Award BIOS v6.00PG
ID: 08/02/2004-nVidia-nForce-6A61BM4CC-00
BIOS-Datum: 08/02/04
Chipsatz: nVidia nForce2 Ultra 400
And now for the very interesting output of the CPU tests (FEHLER = Error, bestanden = passed):
Prozessor FEHLER------------------>
CPU-Kern bestanden
CPU-Register bestanden
Stack-Manipulationen bestanden
Adressierungsmodi bestanden
Prozessor-Flags bestanden
Integer-Arithmetik bestanden
BCD-Operationen bestanden
Bit-Operationen bestanden
Ablaufsteuerung bestanden
String-Operationen bestanden
Prozessor-I/O bestanden
Exceptions bestanden
FPU FEHLER
>FDIV-Bug [alte Pentium]
Laden und Speichern bestanden
Befehlssatz FEHLER
>FDIV-Bug [alte Pentium]
Runden und Abschneiden bestanden
Exceptions bestanden
MMX-Einheit bestanden
Datentransfers bestanden
Gepackte Arithmetik bestanden
Gepackte Vergleiche bestanden
Datenkonvertierung bestanden
Logische Operationen bestanden
Verschiebe-Operationen bestanden
3DNow!-Einheit bestanden
Datentransfers bestanden
Gepackte Arithmetik bestanden
Gepackte Vergleiche bestanden
Datenkonvertierung bestanden
Logische Operationen bestanden
Verschiebe-Operationen bestanden
As you can see, there’s an error within the FPU tests. This is a result, which fits perfectly with the problems I’m seeing. The problem apparently only shows, when a particular instruction is hit. And apparently the Internet Explorer uses exactly this instructions, while most of the other programs don’t use that instruction. As a comparison I also tested my old Duron 1200MHz and the new Athlon 2800+ system and both pass the above test.
It was so frustrating, that all the things, which I tried, to pinpoint the problem, didn’t produce any results. Who knows, where the CPU’s came from, which my dealer gave me, since I distinctively remember that we also replaced the CPU’s back in February. Anyway, as a last confirmation I’m going to install the 2800+ CPU to see, if the problem really has disappeared then. And then I will see, if I can negotiate something with my dealer.