Is my CPU broken? (3800+ X2)

[Bigpops]

I think my A64 X2 3800+ may be faulty. It's about 6 weeks old, and never been clocked. It's a manchester core btw.

Prime 95 fails all standard tests but small FFTs in 2 minutes or less. I ran small FFTs for 7 hours, and it got upto 32K size. At first i thought it may be my memory (which is much older), so i ran a custom test and set memory usage to 0, and FFT size minimum and maximum to 512K (the L2 cache size of the CPU). That failed too, after 11 minutes. I've also had a few BSODs, particularly during Xvid encoding.

Obviously, i need to be virtually 100% certain that my CPU is faulty, so i can RMA it. I'll also have to buy a replacement to use in the mean time. I ran the same setup with a 3500+ winchester for about 18 months with no problems, hence me thinking it's the CPU.

System is as follows:
AMD A64X2 3800+ retail (socket 939)
MSI Neo2 Platinum with bios 1.C3 ballistix mod (though i ran the official 1.B and 1.C too, and it's no different)
2x512MB PC4000 Crucial Ballistix RAM
Leadtek nvidia 6800 AGP
Sb audigy 2 platinum pro
2x 160GB Samsung spinpoints on Sata 3 & 4 (tried with and without raid)
Tagan 480w psu
Windows XP MCE 2005

Is it duff? Are there anymore programs i can use to test it?

 

[trojan698]

Get the memtest 1.65+ bootable iso and try running that.

 

[Mr Mister]

have you installed amd's dual core patch?

 

[kleox64]

If its not your memory Id say its the motherboard, no way it could be your CPU if you have never overclocked it and/or it has ever overheated/run at high temperatures for extended lengths of time.

 

[roadie]

I am having a problem a lot like this too. Please see this thread for more details.

 

[pcoltrane]

I had a similar problem when i upgraded to an x2 3800.

I had been running a 3000+ fine for months beforehand with all the same kit - mem, motherboard etc and it worked well.

Fortunately i had another motherboard to test with and it turned out that the chip was fine - the asus motherboard started to die when i put in the 3800 for some reason. I RMA'd the motehrboard and bought a cheapy to keep me going until it comes back and everything is fine.

It could be the same situation for you - i wouldn't assume that because it all worked with the other chip that it hasn't died since.

Marc

 

[Bigpops]

Thanks for the replies. I'll look into all your suggestions.

I've just ran Memtest 1.65+ for the last hour or so. 4 cylcles of the full default test, and it passed every time.

 

[roadie]

I've just ran Memtest 1.65+ for the last hour or so. 4 cylcles of the full default test, and it passed every time.

Is that single or dual channel?

 

[Bigpops]

Dual channel.

edit: The AMD patch/driver made no difference btw.

 

[roadie]

Gah! My computer only fails Memtest in dual channel mode. I am becoming incredibly frustrated by this POS. Both memory sticks are fine at stock timings and speed so it must be either RAM slot number 2, the CPU or the chipset.

 

[Bigpops]

Quick update, incase anyone else is having similar trouble.

I just picked up a new CPU (3000+ venice) and motherboard (Gigabyte one, based on the Nvidia 6150 chipset) which i'll be using in a media PC soon.

I've swapped the CPU, and prime reacts in exactly the same way as before, so that pretty much rules out the CPU. Now i guess i'll re-build my rig with the new mobo and my 3800+, and do a fresh install on a spare HDD.

 

[Mikey1280]

Btw roadie the Epox 9NPA overvolts by 0.1v so you're really running 1.6v through your Venice. Just thought I'd let you know

 

[Bigpops]

Well, after using 2 motherboards, and 2 cpus in every combination, the result was the same.

So, a quick memory swap (to 512MB oc OCZ PC3200 BH5 i've stolen from my Dad's machine), and everything's fine. So much for memtest 1.65+.

 

[trojan698]

There may not be anything necessarily wrong with the RAM itself, it might just be an incompatible with the board