Originally Posted by erase
Picked up for cheap a Dell XPS 435t / 9000 about a month ago. It is pretty nice machine considering it is over 10 years old. Handles memory like a pro, I can throw in anything and will pick it up no problem. 24 GB or 48 GB no problem.
I recently upgraded with a Xeon W3680, easy to bump up the clocks to 4 GHz with throttlestop, which is enough for me.
The only problem I have it runs it at 1066 MHz, I have only got it twice to boot up at 1333 MHz speed and that was leaving it unplugged the night before, then it will boot one time only at the faster speed. Even if I reduce the amount to just 12 GB, it does the same thing, just 1066 MHz
Is there any way what so ever, I can change the memory speed and force 1333 MHz (or even tweak the timings), hidden setting or a BIOS mod, without changing the entire motherboard?
Not that I'm aware of. Same issue, same board, also with a W3680, latest BIOS. If you ever find a solution, do let me know please.
Should have no issue running 1600MHz C10-C11 or 1333Mhz low latency with any of the RAM I tried according to Thaipoon Burner (even down to the subtimings), and yet I could never get the board to boot with the RAM at any speed other than 1066MHZ C7. I'm surprised it booted over 1066MHz for you at all; I would have guessed 1066MHz C7 is somehow hard coded into the BIOS.
As far as I've read, BIOS mods are not possible because of how Dell checksummed or encrypted (or some such, I don't recall) this BIOS. I can no longer find the url, but if you search, you'll find it soon enough. Perhaps a good BIOS modder like HelpDatBIOS would take a look for you, he/she may be able to do something. Either that or I've been told (by Retrorocket, to give credit) that you can hard mod motherboards similar to GPUs; it's usually done to increase vcore but maybe something can be done to increase RAM speed. Mine is currently used as a file server, so I can't risk bricking it or deal with the downtime of BIOS modding, or I would see about tinkering with it too.
Also if power efficiency matters to you, you might try 3.9GHz vs 4GHz; my chip needed +50w for 4GHz (3.9GHz 150w vs 4GHz 200w).