7750 ddr3 vs 7750 ddr5

Visivicous

Junior Member
Aug 6, 2007
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Title pretty much says it all. I am looking for a budget video card for a friend, and, due to case limitations, it has to be a 1 slot card. After checking the benchmarks over at PassMark, I've settled on the Radeon 7750. Problem is, I found two (1 slot) models which appear to be identical other then the memory type used (the DDR5 one also has a displayport, which does not matter for this build).

DDR3 version:
http://www.newegg.com/Product/Produc...82E16814131481
128-bit, 1GB DDR3, effective memory clock "1600MHz"
$94 including shipping

DDR5 version:
http://www.newegg.com/Product/Produc...82E16814131461
128-bit, 1GB DDR5, effective memory clock "1125MHz (4.5Gbps)"
$105 including shipping

If the DDR5 version will definitely offer some performance gain, I'll go with that (cost is not much greater). But if this is just some gimmick, then I'll go with the DDR3 version.

Knowledgeable advice would be appreciated.
 

Stuka87

Diamond Member
Dec 10, 2010
6,240
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Go for the DDR5 version, period. There is a noticeable performance difference.
 

Red Hawk

Diamond Member
Jan 1, 2011
3,266
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GDDR5 over DDR3 is certainly not a gimmick; the 7750 is meant to use GDDR5 and stepping down to DDR3 essentially cripples it.
 
Aug 11, 2008
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GDDR5 over DDR3 is certainly not a gimmick; the 7750 is meant to use GDDR5 and stepping down to DDR3 essentially cripples it.

I didnt know they even made DDR3 versions. Guess the manufacturers will never miss a chance to save a few bucks and advertise "2gb" memory.

Edit: I agree though, I would not even consider a DDR3 version, get the GDDR5.
 

Visivicous

Junior Member
Aug 6, 2007
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Thanks for the replies. I'll go with the DDR5 version. For some reason I was thinking that the effective memory clock was the more important stat.
 

KompuKare

Golden Member
Jul 28, 2009
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Just to add to this for anyone else asking the same question (these kind of threads are popular google search results after all).

As well as the ht4u.net articel crisium linked to, hardware.fr also did a DDR3 vs GDDR5 7750 comparison:

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http://www.hardware.fr/focus/76/amd-radeon-hd-7750-ddr3-test-cape-verde-etouffe.html

Pretty much the same results, that is 40%-50% slower.
 

SPBHM

Diamond Member
Sep 12, 2012
5,065
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if you want a slower card perhaps you should look at the 6670, 7750 ddr3 makes no sense.
 

Lonyo

Lifer
Aug 10, 2002
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Thanks for the replies. I'll go with the DDR5 version. For some reason I was thinking that the effective memory clock was the more important stat.

It is (when comparing two otherwise identical cards), but they have messed up their effective memory clock figures. You were right, they were wrong.
The effective memory clock of the GDDR5 is 1125Mz x 4 = 4500GHz
The effective mem clock of the DDR3 is 800MHz x2 = 1600MHz

They just decided to display 1125Mhz (4.5Gbps) and 1600Mhz, which is the real clock (effective clock) vs just effective clock.
The inclusion of 1125MHz makes it confusing, since that's not the effective clock, that's the real clock, with real clock being 1/4*effective.

DDR3: Real 800MHz Effective 2x800MHz = 1600MHz
GDDR5: Real 1125MHz Effective 4x1125MHz = 4500MHz