Installed win xp sp2. works ok with 128m. cannot get it work with any more than that. 2 sticks of 256m sdram, ddim manufactured by PNY. checked and rechecked specs. Any insight would be appreciated.

thanks ahead.

It is an old system that requires low density PC100 RAM. I'm guessing you bought PC133. Here's what it says at the PNY website:

"Important: This PC133 Module is not backward compatible with PC100 Machines. To determine the correct memory upgrade for your machine, use the PNY memory configurator."

Here's what you *should* have bought:

http://www2.pny.com/256MB-PC100-SDR...

Differently according to Crucial, I presume a 8860 is actually a PAVILION:

http://www.crucial.com/uk/store/lis...

or maybe KINGSTON:

http://www.ec.kingston.com/ecom/con...

If you can still find low density PC133, go for it. But when you install it, make sure to run it at 100MHz. Your motherboard is based on the KT133 chipset & does not support 133MHz(266FSB) CPUs, so your CPU is either an Athlon T-Bird or Duron SpitFire that runs at 100MHz(200FSB). There's no point running the RAM faster than the CPU. Best performance on a socket A is when both the CPU & RAM run in sync...aka 1:1 ratio...aka both at the same speed.

1st, thanks for everyone's insight. What I have is "256MB PC100/133", "Compatible with 100MHz & 133MHz Bus Speed Systems" I went to PNY site and looked for upgrade module and it gave SN# (256S100) which is the same SN# that's on the package I purchased. Does the module have to say PC100 and nothing else?

Most of the time PC133 will run at PC100. I'd guess the warnings on some that they will only run at 133 just mean they weren't tested at 100. Once or twice I've run those 'pc133 only' at pc100 and they seemed to have worked OK.

Since yours is marked compatible with both it should work, barring the high density chip issue already mentioned.

Are the 256's not recognized at all or are they seen perhaps as 128's?

As the system boots and displays "hardware checks", the 512m (2x256) "passed". When (if) the operating system comes up, I never know when it's going to flake out. I looked at a manual for av7-vm. all I saw was pc100. I found some modules for pc100 on ebay. Will buy and try. Once again, this has been an enlighting exchange. I'm just getting into this hardware stuff, and you guys have turned on many a light. will let you know how this turns out.

Yeah, it may be bad ram. Also make sure the ram sockets and ram stick edges are clean. Make sure the sticks are firmly inserted.

just received and installed pc100 256x2. everything seems ok. System shows 512 and seems to be fine. thanks.

We're glad you got it fixed. Thanks for posting back.

I have an hp 8860 with the same motherboard and it runs fine with the 2 512mb chips at 133 mhz