Hi, I just bought some Kingston HyperX PC8500 RAM form ebay. The box and the sticker on the actual memory actually says it is PC8500... but when I run a check on CPUZ, it actually shows that it is a PC6400... is that normal or have I been scammed? I am running 2x Kingston HyperX PC8500 and also 2x OCZ XMS2 PC6400 Ram. All these rams are actually 1GB each which totals 4GB... it says that on the booting screen but for some reason, when I get into vista, it only shows 2GB... any reason for that?

I may be wrong here but ,,I think that what you are seeing is the SPD detection at work to get the ram to what the sticker indicates you might have to set it in your bios..At least that is what I was told when I queried Kingston about the same thing with their 6400's..
The only reason[s] that I can think of for your not seeing all 4g is::: 1,you need to put the slowest sticks in the first two slots,1a+1b or whatever probably the Kingston,and::2,some mobo's do not play well with 4x1 sticks of ram.....:> )

weird... but i actually get bios readings of 4GB.... how is that ? I mean windows shows 2GB

any ideas?

your mixing 2 different types of memory pc6400 and pc8500.... Your machine is going to go with the lower speeds to try to make it all work..

You need to take out the OCZ memory to get it to run at pc8500

As for not recognizing 4gb.... are you running 64bit? 32bit vista will only see and make use of 3gb+.

Also, with it being different makers and speeds , the mobo may not be able to use the new set just cause its so different.

Im getting the same prob with mine.. im no expert really but my mother board (KA92 Platinum for AM2+) is reading the memory sticks as 800Mhz!

I feel ripped off.. it really says 1066Mhz on the case..

They occupy 2 slots only on my mother board and I still have 2 more available..

I am also running on a windows xp 64 bit OS.. and it reads 4 GBs which is good i guess..

any other ideas and suggestions?

Your memory is probally 1066 , the motherboard reads it as 800 so it will run, its just a standard thing, just go in the bios and set the speed and timings yourself, if its really 1066 it will run fine at 1066.

The problem of 2Gb instead of real 4Gb is in Vista itself. For certain reasons Vista doesn't show the full memory size above 3Gb. This is a known bug.