RAM configuration

[PatrickCT]

Hello

I upgraded this pc a few years ago to 4gb PC -6400 (DDR800) and the Core2Duo 8500. I also upgraded the BIOS which eliminated a boot error due to the new CPU. Coming from less and slower RAM and a much weaker CPU, it was a significant and very noticeable performance increase.

I now have to upgrade the os. Would prefer to go to Win7, but our IT dept wants me to go straight to Win10.

The dc7800 has the Intel Q35 express chipset, with dual-channel ddr2 support. The mbrd has four RAM slots, two for channel A and two for channel B. The max RAM according to the system manual is 8GB. The RAM configurations are:

single-channel mode- RAM in channel A slots only;

dual-channel asymmetric mode-RAM in both channels but of unequal capacities

dual-channel interleaved mode-RAM of equal capacities in both channels.

Each of my channel A slots has 2GB. I want to upgrade to 8GB capacity RAM  without having to replace the present RAM. Is there a way to force the hardware or os to recognise 4GB RAM in channel A and 4GB RAM in channel B as a single capacity of 8GB (effectively as single-channel RAM), not dual channel ?   

regards

Patrick

[Paul_Tikkanen · Accepted solution]

Hi, Patrick:

I have a dc7800 CMT running W10 Pro v1909 just fine.

I am also running it with a 240 GB SSD and 4 x 2 GB of PC2-6400 memory.

I do not believe a 4 GB memory module will work in a slot.

Not to mention that a 4 GB DDR2 memory module will cost way more than 2 x 2 GB, so unless you have a 4 GB DDR2 memory chip handy, it is not financially prudent to buy any--especially if they don't work, which is highly likely they won't.

Or if your company has any dc7900's, a 4 GB DDR2 memory module will work in one of those.

This is the memory I used.

https://www.amazon.com/dp/B07ZGB4553/ref=dp_cr_wdg_tit_rfb

[PatrickCT]

Hi Paul

Thanks.I wasn't expecting such a fast response.

I'm glad to see that Win10 can still run adequately on these machines.

I definitely want to keep my 2X2GB modules, but wasn't bothered about whether I used 2X2GB or 1X4GB for channel B, so thanks for the advice about this. I haven't bought RAM in a long time and am a bit surprised at the cost of this  old memory.

I was under the impression that operating RAM in multichannel config. meant a capacity/bandwidth tradeoff, but I see that I was wrong about this.  That's really good news.

regards

Patrick

[Paul_Tikkanen]

You're very welcome, Patrick.

Maybe you can find equivalent memory cheaper someplace else.

Sometimes older memory costs more because the chip manufacturers make less of it as time goes on.

I have just used the Crucial memory configurator for the dc7800 CMT, and here is what it reports...

https://www.crucial.com/usa/en/compatible-upgrade-for/HP-Compaq/dc7800-series-convertible-minitower

I entered the 2 x 2 GB Crucial kit part # in the New Egg site below and found a kit for $16.72.

https://www.newegg.com/crucial-4gb-240-pin-ddr2-sdram/p/0RN-0005-00GY4?Description=CT2KIT25664AA800&...

[PatrickCT]

Hi Paul

The crucial memory configurator is useful. I have crucial 2X2GB  DDR2 800 RAM, as spec'd by the configurator. I bought more from ebay. They'll take some time to get here but no problem. 4GB will do in the meantime.

Did you use whatever latest 7800 drivers you could find for Win10?

regards

Patrick

[Paul_Tikkanen]

Hi, Patrick.

Yes, use the W7 drivers for the couple devices W10 won't install.

If you need help finding drivers for the couple devices that may not get installed, please let me know.

I actually found that the W7 Soundmax driver worked better than the generic W10 audio driver that W10 installed.