Hardware PC not POSTing after CPU upgrade with 3-4 Ram Slots used

MattS

TS Evangelist
Hi,

I just bought the ryzen 3700x and setup everything except I cant get my pc to post with 4 dimm slots. The pc lights up but doesn't get to the bios. With 2 dimm slots the pc works perfectly.

Ive tested all the ram together separately and they all work perfectly. Re-seated to check all mobo ram slots work and also works. XMP in bios works OK and I'm able to hit 3200mhz as advertised on the Ram.

Now all these ram are of the same brand Corsair vengeance 16-18-18-36 3200MHz

Also prior to removal these were all functional on my ryzen 1700.

I tried to lower clocks with no avail.

System specs are

Ryzen 3700x

Asus Prime b350 plus

And the 4 ram dimms which ive mentioned.

Could it be the timings? I'm going to try and reseat the cmos for a default configuration even though I've tried default settings already but someone suggested this. If this doesn't work does anyone have any idea?

I'm on the latest BIOS available btw.
 

Cycloid Torus

Stone age computing - click on the rock below..
Check manual, QVL - in some rare cases, certain RAM can only be used as a pair and does not function as a double pair. It could be timing and it could be voltage. You may have success seeking technical support from Corsair.
 

MattS

TS Evangelist
So I was mistaken when I tryed thecurrently slotted ram from channel 1 to channel 2 slots 3-4 the pc doesnt really boot.

Power is definetly reaching them tho bcuz theyre heating up but no Post on the second channel even with 2 dimms alone
 

Cycloid Torus

Stone age computing - click on the rock below..
To confirm:
- 4 sticks RAM - all work in slots for channel 1, but all do not work in slots for channel 2
- if you put RAM in slots for channel 2 then NO POST

Leads me to believe that slots for channel 2 on motherboard is in fact the issue. This may be a 'defective motherboard' issue. Before you contact Asus about the motherboard, you might want to examine slots with magnification and under strong light - I once found a metal clipping which had fallen into a slot - and removal restored function. Check underneath too - a loose screw is also a possibility.
 

MattS

TS Evangelist
To confirm:
- 4 sticks RAM - all work in slots for channel 1, but all do not work in slots for channel 2
- if you put RAM in slots for channel 2 then NO POST

Leads me to believe that slots for channel 2 on motherboard is in fact the issue. This may be a 'defective motherboard' issue. Before you contact Asus about the motherboard, you might want to examine slots with magnification and under strong light - I once found a metal clipping which had fallen into a slot - and removal restored function. Check underneath too - a loose screw is also a possibility.

What confuses me though is that I've had everything running on my ryzen 1700 I didn't change anything except the cpu.
 

Cycloid Torus

Stone age computing - click on the rock below..
"Stuff" happens. All we poor mortals can do is follow a troubleshooting tree, keep exact notes and replace bad parts/drivers.
 

MattS

TS Evangelist
"Stuff" happens. All we poor mortals can do is follow a troubleshooting tree, keep exact notes and replace bad parts/drivers.
I'll give it a proper cleaning if this doesn't work I sent a msg to corsair and asus for some troubleshooting assistance.

I was planning to upgrade to a b550 mobo when they're released anyway as VRM on this one ain't that good to sustain the ryzen 3700x
 

MattS

TS Evangelist
Which echoes the possibility that a small adjustment to voltage might be needed.
Tried pushing DIMMs with 1.35V. I guess I should've tested 1.4 or atleast 1.425 I'll give it a shot. the ram modules have some good heat management. Worth a shot!
 

MattS

TS Evangelist
Update on the matter.

Asus responded to check QVL. Ram modules aren't listed for Quad Dimm seems like the mobo is limited to two for ryzen 2 on these modules.

So I'm guessing I'm either stuck till a new bios adds support for 4 dimms or buying a new mobo?