Upgrading Memory

[RasterBlaster]

Kizo,

This is from the dc7900sff hardware guide:

For proper system operation, the DDR2-SDRAM DIMMs must be:

• industry-standard 240-pin
• unbuffered PC2-4200 533 MHz
• The DDR2-SDRAM DIMMs must also:
• 1.8 volt DDR2-SDRAM DIMMs
• support CAS latency 4 (CL = 4) for DDR2/533 MHz

In addition, the computer supports:

• contain the mandatory JEDEC SPD information
• 256Mbit, 512Mbit, and 1Gbit non-ECC memory technologies
• single-sided and double-sided DIMMS
• DIMMs constructed with x8 and x16 DDR devices;

T5ZUBEX,

You are looking at the wrong motherboard specification. HP has lots of different P4SD-LA boards in various configurations. You need to use the HP Name as shown on the m487.uk product specification or simply look in the porduct specifications section of the m487.uk support site.

Here is the link to your real motherboard spec - the Oxford. http://support.hp.com/us-en/document/c00063272

Two 184-pin DDR DIMM sockets

Up to 2GB memory (the PC manufacturer's recommended maximum memory may differ)

Non-ECC 2.5V DDR SDRAM

Register DIMM not supported

This tells me you can install 2 x 1 GB DDR. Do not get registered, buffered, or fully buffered memory.

[nimrod46]

My HP Pavilion 7916 Desktop PC has two memory banks and was supplied with one 128MB SDRAM which I want to upgrade.  The product specification quotes a maximum memory of 512MB with a maximum of 256MB per memory bank.  I have replaced the single 128MB SDRAM with two 256MB SDRAM.  Whilst the computer appears to be operating satisfactorily it is only registering an installed memory of 256MB (128MB per memory bank), half what I expected.  Any suggestions why and how I can correct this will be appreciated.

[RasterBlaster]

Did you buy ECC memory? From the BIOS, you are only seeing 128MB per bank?

168-pin DIMMs

133 MHz

Non-ECC (64-bit)

3.3 V memory only

[joeyp72]

first off my specs

HP media center edition m8400f

3gb ram

vista home premium

I recently upgraded to Win 7 home premium (fresh install) and decided to upgrade my memory. Bought Corsair's XMS2 4gb dual channel kits (x2) but when I turned my computer on, it would run for a short time, maybe 10-15 mins, then either lock up or BSOD on me. I would have to hard restart it. I ran memtest on it and got over 72000 errors before it locked up again. Someone said to change my settings on my bios. It is locked and I cant access the memory settings. I removed 2 pcs of memory and it seemed to run fine, but would lock up after about 5 mins of light gaming. I was advised by someone that it is probably getting way too hot. Could this be a reason for the crashes and if so, do I just get different ram and if so which kind? Thanks in advance.

[RasterBlaster]

How does it behave when only the original memory is installed? If it still locks up, then one of the original DIMMs might have ESD damage.

If the original DIMMs work fine, then there are a few possiblities:

• New memory not fully compatible with your mobo. find DIMMs that exactly match you old DIMM specs.
• Power consumption problems - too much power draw from new sticks. Upgrade power supply as well.
• Heat (unlikely).

[joeyp72]

It works fine with the 2 new memory sticks until I try gaming, then lock up or auto restart. I pulled those out and reinstalled my old sticks. Things work fine again. I had bought Corsair XMS2 6400 4gb kits. I have been looking through some more forums and manufacturers and have found that Kingston is the best match for my system because of the lower profiles of the sticks. My power supply is a PC Power 500 psu just put in about 6 mos ago.

[RasterBlaster]

The profile should not matter as you have a full ATX case - profile is only about the height of the DIMM and really only comes into play for slimline chassis or when room is getting tight. Sounds like you should be good on power supply. If you still have the old power supply, that might come in handy as you can swap it for testing purposes if needed.

There are several varieties of the XMS kits with various CAS latency values. It seems that newer, lower CAS latency values might not play well in some mobos from 2008 or earlier (this is speculation on my part at this point).

Here is the memory spec for your motherboard (Nettle3). Based on the info you have given us, this it looks like the memory you purchased should work.

Dual channel memory architecture

Four 240-pin DDR2 DIMM sockets

Supported DIMM types:

• PC2-5300 (667 MHz)
• PC2-6400 (800 MHz)

Non-ECC memory only, unbuffered

Supports 2GB DDR2 DIMMs

Supports up to 8 GB on 64 bit PCs

Supports up to 4 GB* on 32 bit PCs

Other information that might help:

Does the full amount of memory show up in BIOS?

Did you upgrade the operating system?

Your system originally came with 3GB. What configuration are you trying for? 2 sticks of 2 GB DIMMS in banks 1 and 3 (on a 32-bit OS? this will get you about 3.5GB).

[joeyp72]

Thanks for replying. Originally it came with 2 1gb sticks in the first 2 slots and 512s in the other 2. I was wondering if when I put the new pairs in if it mattered if the were next to each other or not, if that was the problem. The BIOS shows 3070gb now with the old memory back in. It would show the 8gb back when i had them. I had recently done a clean install of Win 7 x64 home premium. The case is a mid sized tower with not a ton of room, that is why I was looking at the lower profile memory. The memory bank is right behind/below the hard drive cage. As far as the CAS, I believe this new Corsair memory is rated at a 6.

[RasterBlaster]

This is what I would do.

Remove the old sticks and put your new memory into slots 1&2. Turn on the  PC, press F8 key at boot, repair... run the Windows 7 memory test (before loading Windows 7).

If it still gives you memory error, try it again with only one of the new DIMMs installed... then swap and test again, to see if one of the sticks is bad.If they both fail with tons of errors, it's probably a compatibility thing. If one of the sticks fail, you've got a bad stick and it should be returned/replaced.

[joeyp72]

Ok, now the dumb question of the day... which slot is designated as #1, near of away from the CPU? I cant find a definite answer about that. :robothappy:  

**found it, sorry. looked at the wrong computer 😞