springen

I have a five year old MESH PC (XP Pro SP2) with an ASUS A7V8X motherboard and AMD Athlon XP 2400+ cpu. After working fine it now refuses to boot. It only gets as far as the 'boot menu', and any option, including safe mode will not work. It will not even boot from floppy and even booting from the Windows setup cd fails.

After much trying, I eventually got it to bring up Windows after I disabled cpu level 1 cache in the bios. It is unusable in this state as windows runs really really slow.

What is going on here - has the cpu had it ? Before you ask, no I haven't overclocked it and it hasn't overheated.

Is there anything else I could try before I condemn it to the bin ??

alabamaman79

Well, the PC is 5 years old so it's not out of the realm of possibility that the CPU is dying. You could just get a new CPU and see if that fixes the problem.

smz

Going back in time actually way back. I have had the same problem with multiple machines. This was in a corporate environment and it didn't seem at the time performance was greatly affected. This was the external CPU cache and not Internal. Unless I misread your post. If it's internal CPU cache then your performance will be horrible.

Someone can come on and chime in whether what he claims as level 1 is internal or not. But regardless, it isn't a good sign. That motherboard is a pretty reliable one. I've had great luck with the Asus A7Vxxx line of products.

springen

Disabling level 1 or level 2 or both, had the same affect - an incredibly slow system. What's difference between level 1 and level 2 anyway ?

As Windows does actually come up can I assume that the Harddrive, motherboard and RAM are OK, and that the CPU is likely to be the faulty component ? I did wonder whether it was a power supply problem, but I have tried substituting another PSU, but it had the same results.

smz

As for your question about level 1 and level 2.
Here's the long answer

The Short answer is: (Level 1 cache) A memory bank built into the CPU chip or packaged within the same module as the chip. Also known as the "primary cache," an L1 cache is the fastest memory in the computer, and it is closest to the CPU. The L1 cache feeds the processor.

(Level 2 cache) A memory bank built into the CPU chip, packaged within the same module or built on the motherboard. The L2 cache feeds the L1 cache, and its memory is slower than L1 memory. The L2 cache feeds the L1 cache, which feeds the processor.

So you can see where there is a performance hit. Is everything thumbs up with your CPU heatsink and fan? Has it see any compressed air in the last 5 years?

springen

Thanks for your reply.

I have never removed the fan/cpu. The cooling fan still runs no problem. When it was working I used to check temperatures etc with pcprobe - no problems. No I have never 'blown' it out. The PC was running fine one evening, I shut it down , then 24 hrs later the problems started - so it was from a cold start, it wasn't as if it packed up while getting hot ??!!

I guess it would be sensible to change CPU and motherboard, in case problem is related.

smz

well attempting to boot a different CPU in the exact same environment lets you narrow down the issue to computer hardware (most likely the m/b) or the cpu. Thats the nice thing about us Tech guy's with a bench, when we've got alot of spare components laying around, troubleshooting is a breeze. but it doesn't always work out that way for the casual user... if you can somehow obtain access to a different cpu that is supported by your board, it's worth a try, but make sure you setup the cpu in bios and set any jumpers if necessary on the board. With your configuration, the only thing i've seen on boards as far as jumpers is some rare motherboards that want you to set the FSB on the m/b before starting up.

springen

Problem fixed - well sort off.

I removed all the memory cards and then replaced them one by one after each boot. After lots trying, I have deduced that all the memory cards are OK, but two of the 'slots' no longer work. The 3 slots originally contained a 256, 256, 512. Now only slot one works with the 512. If I try and put another memory card in one of the other slots the 'no-boot' problem comes back. Although they all work if placed individually in slot 1.

What caused this ? - I have no idea. Anyway thank you for your help.

smz

well there are rules that a motherboard manufacter will post regarding what slots can have memory in them while others are populated. if you have your manual, you will probably see some kind of graph about SS and DS single side/double sided. perhaps you put your memory back in different slots?